Nvidia driver not working in ProMepis

Using ProMepis 2005.b3, on my Compaq Presario R3140us, which includes a 1280x800 screen and nvidia geforce4 420 go with 32mb, after installing the glx package, editing the config file, etc. etc., the driver doesn't work. I get a blue square with a line at the bottom. It worked very well with SimplyMepis.

I suspect it is the driver and the later nvidia kernel, not hardware. Has anyone else had this problem?

Can I revert to the older kernel and still get all that ProMepis goodness? Otherwise I will reload Simply Mepis and upgrade to KDE 3.3 and skip gnome (I don't use it anyway).