diff --git a/autoload/vimwiki/html.vim b/autoload/vimwiki/html.vim
index 17c4b59..f2b55bb 100644
--- a/autoload/vimwiki/html.vim
+++ b/autoload/vimwiki/html.vim
@@ -49,8 +49,8 @@ function! s:is_img_link(lnk) "{{{
   return 0
 endfunction "}}}
 
-function! s:default_CSS_full_name(target_dir) " {{{
-  return vimwiki#path#join(path, vimwiki#vars#get_wikilocal('css_name'))
+function! s:default_CSS_full_name(path) " {{{
+  return vimwiki#path#join(a:path, vimwiki#vars#get_wikilocal('css_name'))
 endfunction "}}}
 
 " Returns: 1 if it was created, 0 if it already existed
@@ -72,7 +72,7 @@ function! s:template_full_name(name) "{{{
     let name = a:name
   endif
 
-  let filename = vimwiki#path#from_segment_file(name . vimwiki#vars#get_wikilocal('template_ext'))
+  let filename = vimwiki#path#file_segment(name . vimwiki#vars#get_wikilocal('template_ext'))
 
   let template_file = vimwiki#path#to_string(vimwiki#path#join(vimwiki#vars#get_wikilocal('template_path'), filename))
 
diff --git a/autoload/vimwiki/path.vim b/autoload/vimwiki/path.vim
index 94aa725..08036f9 100644
--- a/autoload/vimwiki/path.vim
+++ b/autoload/vimwiki/path.vim
@@ -169,19 +169,28 @@ endif
 
 
 "----------------------------------------------------------
-" Path manipulation, i.e. do stuff with the paths of (not necessarily existing) files
+" Path manipulation, i.e. functions which do stuff with the paths of (not necessarily existing) files
 "----------------------------------------------------------
 
 
-" The used data types are (with their internal representation)
-" - directory object: a dictionary with the following entries:
-"     - 'protocoll' -- how to access the file. Supported are 'scp' or 'file'
-"     - 'is_unix' -- 1 if it's supposed to be a unix-like path
-"     - 'path' -- a list containing the directory names starting at the root
-" - file object: a list [dir_obj, file name]
-" - file segment: representing e.g. a relative path. Is a list where the first
-"   element is a list of directory names and the second the file name
-" - directory segment: a list of directory names
+" The used data types are
+"
+" - directory object:
+"    - used for an absolute path to a directory
+"    - internally, it is a dictionary with the following entries:
+"      - 'protocoll' -- how to access the file. Supported are 'scp' or 'file'
+"      - 'is_unix' -- 1 if it's supposed to be a unix-like path
+"      - 'path' -- a list containing the directory names starting at the root
+" - file object:
+"    - for an absolute path to a file
+"    - internally a list [dir_obj, file name]
+" - file segment:
+"    - for a relative path to a file or a part of an absolute path
+"    - internally a list where the first element is a list of directory names and the second the
+"      file name
+" - directory segment:
+"    - for a relative path to a directory or a part of an absolute path
+"    - internally a list of directory names
 
 
 " create and return a file object from a string. It is assumed that the given
@@ -214,6 +223,21 @@ function! vimwiki#path#dir_obj(dirpath)
 endfunction
 
 
+" Assume it is not an absolute path
+function! vimwiki#path#file_segment(path_segment)
+  let filename = fnamemodify(a:path_segment, ':t')
+  let path = fnamemodify(a:path_segment, ':h')
+  let path_list = (path ==# '.' ? [] : split(path, '\m[/\\]', 1))
+  return [path_list, filename]
+endfunction
+
+
+" Assume it is not an absolute path
+function! vimwiki#path#dir_segment(path_segment)
+  return split(a:path_segment, '\m[/\\]', 1)
+endfunction
+
+
 function! vimwiki#path#extension(file_object)
   return fnamemodify(a:file_object[1], ':e')
 endfunction
@@ -231,16 +255,26 @@ function! vimwiki#path#filename(file_object)
 endfunction
 
 
-" Returns: the dir_obj or file_obj as string, ready to be used with the regular
-" path handling functions in Vim
+" Returns: the dir_obj, file_obj, file segment or dir segment as string, ready
+" to be used with the regular path handling functions in Vim
 function! vimwiki#path#to_string(obj)
-  let dir_obj = type(a:obj) == 4 ? a:obj : a:obj[0]
-  let separator = dir_obj.is_unix ? '/' : '\'
-  let address = join(dir_obj.path, separator) . separator
-  if type(a:obj) == 3
-    let address .= a:path[1]
+  if type(a:obj) == 4   " dir object
+    let separator = a:obj.is_unix ? '/' : '\'
+    let address = join(dir_obj.path, separator) . separator
+    return address
+  elseif type(a:obj[0]) == 4  " file object
+    let dir_obj = type(a:obj) == 4 ? a:obj : a:obj[0]
+    let separator = a:obj[0].is_unix ? '/' : '\'
+    let address = join(a:obj[0].path, separator) . separator . a:obj[1]
+    return address
+  elseif type(a:obj[0]) == 3  " file segment
+    " XXX: what about the separator?
+    return join(a:obj[0], '/') . '/' . a:obj[1]
+  elseif type(a:obj[0]) == 1  " directory segment
+    return join(a:obj, '/') . '/'
+  else
+    call vimwiki#u#error('Invalid argument ' . string(a:obj))
   endif
-  return address
 endfunction
 
 
@@ -251,38 +285,30 @@ function! vimwiki#path#append_to_dirname(dir_obj, str)
 endfunction
 
 
-" Assume it is not an absolute path
-function! vimwiki#path#from_segment_file(path_segment)
-  let filename = fnamemodify(a:path_segment, ':t')
-  let path = fnamemodify(a:path_segment, ':h')
-  let path_list = (path ==# '.' ? [] : split(path, '\m[/\\]', 1))
-  return [path_list, filename]
-endfunction
-
-" Assume it is not an absolute path
-function! vimwiki#path#from_segment_dir(path_segment)
-  return split(a:path_segment, '\m[/\\]', 1)
-endfunction
-
-function! vimwiki#path#join(dir_path, file_segment)
-  let new_dir_object = copy(a:dir_path)
+" Returns a file object made from a dir object plus a file semgent
+function! vimwiki#path#join(dir_obje, file_segment)
+  let new_dir_object = copy(a:dir_obj)
   let new_dir_object.path += a:file_segment[0]
   return [new_dir_object, a:file_segment[1]]
 endfunction
 
+
+" Returns a dir object made from a dir object plus a dir semgent
 function! vimwiki#path#join_dir(dir_path, dir_segment)
   let new_dir_object = copy(a:dir_path)
   let new_dir_object.path += a:dir_segment
   return new_dir_object
 endfunction
 
-" returns the segment s, so that join(dir, s) == file
+
+" returns the file segment fs, so that join(dir, fs) == file
 " we just assume the file is somewhere in dir
 function! vimwiki#path#subtract(dir_object, file_object)
   let path_rest = a:file_object[0].path[len(a:dir_object.path):]
   return [path_rest, file_object[1]]
 endfunction
 
+
 " Returns: the relative path from a:dir to a:file
 function! vimwiki#path#relpath(dir1_object, dir2_object)
   let dir1_path = copy(a:dir1_object.path)
@@ -331,7 +357,7 @@ let s:vimwiki_autoload_dir = expand('<sfile>:p:h')
 
 function! vimwiki#path#find_autoload_file(filename)
   let autoload_dir = vimwiki#path#dir_obj(s:vimwiki_autoload_dir)
-  let filename_obj = vimwiki#path#from_segment_file(a:filename)
+  let filename_obj = vimwiki#path#file_segment(a:filename)
   let file = vimwiki#path#join(autoload_dir, filename_obj)
   if !vimwiki#path#exists(file)
     echom 'Vimwiki Error: ' . vimwiki#path#to_string(file) . ' not found'
diff --git a/autoload/vimwiki/tags.vim b/autoload/vimwiki/tags.vim
index 9582df5..0a76019 100644
--- a/autoload/vimwiki/tags.vim
+++ b/autoload/vimwiki/tags.vim
@@ -145,7 +145,7 @@ endfunction " }}}
 " vimwiki#tags#metadata_file_path
 "   Returns tags metadata file path object
 function! vimwiki#tags#metadata_file_path() abort "{{{
-  return vimwiki#path#join(vimwiki#vars#get_wikilocal('path'), vimwiki#path#from_segment_file(s:TAGS_METADATA_FILE_NAME))
+  return vimwiki#path#join(vimwiki#vars#get_wikilocal('path'), vimwiki#path#file_segment(s:TAGS_METADATA_FILE_NAME))
 endfunction " }}}
 
 " s:load_tags_metadata
diff --git a/autoload/vimwiki/vars.vim b/autoload/vimwiki/vars.vim
index b907c20..8d2af46 100644
--- a/autoload/vimwiki/vars.vim
+++ b/autoload/vimwiki/vars.vim
@@ -48,6 +48,8 @@ function! s:populate_global_variables()
     endif
   endfor
 
+  call s:validate_global_settings()
+
   " non-configurable global variables
 
   " Scheme regexes should be defined even if syntax file is not loaded yet cause users should be
@@ -152,6 +154,27 @@ function! s:populate_global_variables()
 endfunction
 
 
+function! s:validate_global_settings()
+  let g:vimwiki_global_vars.dir_link =
+        \ vimwiki#path#file_segment(g:vimwiki_global_vars.dir_link)
+
+  for extension in g:vimwiki_global_vars.ext2syntax
+    if extension[0] != '.'
+      let g:vimwiki_global_vars.ext2syntax['.'.extension] =
+      g:vimwiki_global_vars.ext2syntax[extension]
+      call remove(g:vimwiki_global_vars.ext2syntax, extension)
+    endif
+  endfor
+
+  let new_user_htmls = []
+  for file_name in split(g:vimwiki_global_vars.user_htmls, ',')
+    let trimmed = vimwiki#u#trim(file_name)
+    call add(new_user_htmls, vimwiki#path#file_segment(trimmed))
+  endfor
+  let g:vimwiki_global_vars.user_htmls = new_user_htmls
+endfunction
+
+
 " g:vimwiki_wikilocal_vars is a list of dictionaries: one dict for every registered wiki plus one
 " (the last in the list) which contains the default values (used for temporary wikis).
 function! s:populate_wikilocal_options()
@@ -213,12 +236,16 @@ function! s:populate_wikilocal_options()
   let temporary_options_dict.temp = 1
   call add(g:vimwiki_wikilocal_vars, temporary_options_dict)
 
-  call s:validate_settings()
+  call s:validate_wikilocal_settings()
 endfunction
 
 
-function! s:validate_settings()
+function! s:validate_wikilocal_settings()
   for wiki_settings in g:vimwiki_wikilocal_vars
+    let wiki_settings.css_name = vimwiki#path#file_segment(wiki_settings.css_name)
+
+    let wiki_settings.custom_wiki2html = vimwiki#path#file_object(wiki_settings.custom_wiki2html)
+
     let wiki_settings['path'] = vimwiki#path#dir_obj(wiki_settings['path'])
 
     let path_html = wiki_settings['path_html']
@@ -231,7 +258,7 @@ function! s:validate_settings()
 
     let wiki_settings['template_path'] =  vimwiki#path#dir_obj(wiki_settings['template_path'])
     let wiki_settings['diary_path'] =  vimwiki#path#join_dir(wiki_settings['path'],
-          \ vimwiki#path#from_segment_dir(wiki_settings['diary_rel_path']))
+          \ vimwiki#path#dir_segment(wiki_settings['diary_rel_path']))
   endfor
 endfunction
 
@@ -606,7 +633,7 @@ function! vimwiki#vars#add_temporary_wiki(settings)
     let new_temp_wiki_settings[key] = value
   endfor
   call insert(g:vimwiki_wikilocal_vars, new_temp_wiki_settings, -1)
-  call s:validate_settings()
+  call s:validate_wikilocal_settings()
 endfunction
 
 " number of registered wikis + temporary