[mattjb]

I've installed PCLinuxOS Gnome 2008 Compiz-Fusion on both my laptop and desktop; both seem to exhibit the same behavior regarding alt-mousewheel to change the transparency on a window.

It's possible to change the transparency for me, but I have to scroll like 50 times or so just to get it to get it to the first stage of transparency, is there some additional configuration that needs to be made in order to make one mousescroll action to be one grade of transparency?

[don_crissti]

is there some additional configuration that needs to be made in order to make one mousescroll action to be one grade of transparency?

It seems you have a problem there as I just tested this thing and it works OK here: ALT+mousewheel turns transparency off/on in one "complete" scroll.
Try tweaking it from Compiz settings > General > Opacity Settings > Opacity Step