its under developement but you grab it here (It improves on trollparty.css using also colors from matrix themes)
If you want to develop your own themes trollparty.css and other that don't have templates are the easiest. Assuming you want to change a theme with no templates, I suggest you go to a section with your browser, right click and grab the code and save it in your local drive, change the path to the .css accordinlgy and start changing things and testing to see results.
Send me a message if need further help or go to http://mods.tiki.org for guides on how to get started or to discuss issues/suggestion on improving the themes/mods of tikiwiki.
I am posting some comments here while I am trying to understand the best avenue to post requests/bugs and start tweaking the code.
The truth is there is the sourceforge bugs/requests and then there is the forums in here and then there is the wikis which I am struggling to put into some order, I get the feeling that some of the reports overlap ?
Some kind of map on who is working on what would not hurt so maybe people could assign bugs directly to developers ?
Definetelly need some reorganization of the adminstrators side of view.
URL could be friendlier like tikiwiki.org/articles/23/45 instead instead of tikiwiki.org/tiki-viewarticle.php?articleid=23. I understand this probably needs a lot of change in many places of the code so might be kind of more difficult). Marc offered the hint to look at TikiWikiRewriteRule and Rewrite Rules in documentation pages (did not have time to do that yet)
Some visual editing of the layout would be great as a matter of fact.