How to on/off layer & have scrolls inside

Hi sorry for posting this, but I'm loosing my patience with trying to figure
this out (and I don't know the solution yet):

I have a few scripts that do:

'Switch layer on and off' and also 'Scroll content'

My problem is that I build sites that are to be seen in all different
browsers (I have a php index page that checks the browser type and version
and opens another htm index file with the site, it's very quick and
efficient), and I'm building a web site that uses only html and no flash at
all.
The web page in question, opens and shows a few words that behave like
links.
When you click on the links a layer opens with all the info (content), and
Since the content is bigger than the layer (window constraints, aesthetics
and so forth) I thought of having a scroll in the layer, so that content can
be scrolled up and down (very straight forward).
But.
For some reason I can't get the page to work in different web sites. Only in
safary (mac browser). So it might be that I'm using the wrong script (I've
gathered stuff from the net, cut and stiched, patched and got this one which
is unfortunately not well written, cos it's not compatible with other
browsers, or it simply doesn't work).
I can show it to you, but since I believe it's wrongly written I'd prefer to
get advice on it or an indication to some website that has a script that
does this job.

Thank you very much for any kind of help you can give me.

Cheers


tiago