Interestingly, what you are posting as “an issue” is actually one of the nice things about using a framework in general.
When you do the “quick install” of the t3 framework and don’t install the sample content, you basically have a blank white page with a few grey lines on it (in 2.5 you have the red theme selected by default). What you have then is the ability to easily (?) layout your modules and such using the module positions.
The “override” css is only necessary for the styles you want to override, they otherwise have little to no styling to remove. I build my templates (or themes to the t3 blank template, I suppose) this way, using the graphics I create in Xara Designer Pro sliced out, and the colors and fonts that I have designed for as the backgrounds, etc.
It takes a bit to get your head around the whole thing, but once you do, you may find (like me) that there’s little need to create sites in html/css any more. these “grids” have already been tested across browsers and that’s one less thing I have to concern myself with, instead being able to focus on the design instead.
The base theme is basically “un design”, so it’s pretty easy to make it whatever you want it to be, only having to override the very specific things that you actually use.
Have more specific questions? Ask away!
Scott Lavelle - Technical Resource Solutions, LLC
Certified Joomla Administrator