I've moded my CMS (DEV1.2.3) with the RT POPUP by pixelpeter. But the RT not quite fits my needs. Maybe somebody can help me doing the following enhancements. (But im more a designer than a coder

I wanna give visitors of a university site the ability to read additional info about a special word of topic.(not a regular link). So i decided to use the RT[POPUP].This Popups should show separate articles (hidden from menu)
Example:
Home |
-- Level:Popups [ID:11]
|
----------Article:Pop1 [Articel-ID:31]
----------Article:Pop1 [Articel-ID:32]
I noticed that the RT can't show the articles in the sublevel but the Level with the first Article in it. This means the correct usage of the RT is:
[POPUP:LEVELIDOrAlias:width:height]linkText[/POPUP]
Enhancement:
1.) how to modify the php-code (and in which file) for using the Articel-ID as the call-variable?
2.) How to add a css-style to the php-code <a class="popup"> ..</a> for styling the popup-link permanently?
3. ) How to prevent showing special chars (Ä,Ü,ß) as system chars (ä,ü,ß) by using a different Contentparts as simple text?
Thanks a lot. le block