Really Technical Problem

[son of teh]

Ugh... I've finally been getting around to play Planescape Torment but now I'm having a technical problem. Basically I had already installed the game once, but ran into a bug and stopped. So I got the patch, and also decided to get some mods. Well I must have done something wrong cause I screwed up my install, so I uninstalled Planescape completely and deleted the old folder. So, I reinstalled Planescape. However, now when I try to install the patch it doesn't work, it unpacks it but the install screen never comes up. I'm pretty sure this is a registry problem, it thinks the game is already patched since it had been patched before. Does anyone know what key to delete to stop this? Or maybe some other way around it? Is there any patch for Torment that's available in a form other than those "PackageForTheWeb Stub" form? This is pretty aggravating!