I am still trying to find out why this broke between versions. It should work but it one of those:

They're not bugs...it's either un-defined features or exceptions to expected behaviour!!

Is this being addressed now or are we hoping this is fixed in the 4.5 release?  If so, I'm stuck launching my site until this is corrected.  I have grown frustrated trying to find a consistent method of applying styles via the custom config js, mystyles.xml nd mystyles.css method desribed in the developers guide.  No matter what I do inside the cstom editor options page, I never get the provider to do what it should do.  I have used the url command, put the custom js, custom xml and custom .css in the same folder as the originals (just for simplicity) and I have applied it to the entire portal.  If I view my site as an unauthenticated user, my text and styles are not applied at all.  If I edit the text within the module, the editor shows the styles being applied and the styles drop down box is populated with my styles.  If I make changes to my css (such as change the font size of one of my custom styles) it does not take effect in the editor or in non-editing mode.  Here is what I did:

Copied the js file and placed the copy in the same location as the original.

Changed the original config js to point to the custom config js.

Copied the original fckeditor.xml file and placed the copy into the same location as the original.  Renamed the file and added some styles.

Made my own css file and placed it in the same location as the above files.

Opened up the editor on one of my pages and went into show customize editor options.

Expanded "List of available editor options and chose url.

Uploaded my custom xml file by choosing "file on my site"

Chose use exisitng file.

Did the same process by expanding editor area css and choosing my custom css file.

Went to my custom config.js file and changed the following line from: