Well, I tried the installer (which, interestingly enough, gave me a whole new graphic for the laser... red, as opposed to blue.) And all was well.
But that would be too easy.
And I know there was a reason I didn't want to use the installer (it was the first SCP install I did... I deleted it and went on my way) if only I could remember what my reason WAS....
Anyway. I re-downloaded all the ZETA MediaVPs and the 710 patches and shoved those into my mediavps folder after deleteing all the old ones (same files, downloaded at the same place) and now... all seems well. Everything works. I even like the engine glow.
And all in OpenGL (which is STILL screwing up my ability to watch DivX files, but that is probably my GeForce cards fault. =/ Or a driver issue) too!
Thanks for all your help everyone!