How to run two or more themes simultaneously in same blog?

Hello,

This is a bit hard to explain, but, the thing is:

I would like to have two themes in my blog, one main theme and one alternative (lite-version in my case). I want it to be like main theme in my main address (http://www.rollemaa.org/index.php) and alternative theme in address like http://www.rollemaa.org/lite/ so that two themes are on at the same time without user having to switch theme, the theme would be on by going to that address.

CSS-style switcher -script would do it, but I already have one in my main wordpress-theme, and somehow the main style-sheet is overriding the others (they only have couple of lines which do the changes, in my case the season-type of layouts).

I tried making template in my theme-directory, lite.php and lite.css, and made the layout there and made new page from wp-admin and added custom template from there but when I was trying to make a post loop it printed out the page title and timing…. and I want the blog posts there, not the page title/text -content, and I also would like to have other pages (comment-page) in lite-theme, not only the main page.

I’m not good at explaining this, but I hope you understand. Tried googleing with many keywords but it was hard because the results were about free wordpress themes or template tags and so on…

So, let’s repeat it: I now have my main theme (of course) in address http://www.rollemaa.org/index.php , and I would like to have lite-version of my site’s layout in http://www.rollemaa.org/lite/

Is this even possible?
Any help would be really appreciated!

Kindly,
Rolle