1--I have windows 7 and XSI 5.0 foundations. When i try to install the fixed pandemic xsi addon, it doesn't work.
the normal pandemic xsi addon installs and shows up, but doesn't work. Teh FBX addon works.
The tools don't work in XSI 5.1 either.

picture of error on export Pandemic addon from HERE

2--I tried to install XSI 6.0, 6.1, and 7.5, but it gave me some error about pixels.

is there some way to fix either problem?

From a topic on the same problem with Vista. might work
HERE

I tried the CMD.exe with the given code, didn't work it said Regsvr is not a recognized command. i tried a new code the [/i] is supposed to use the regsvr to update/install .dll, but it tells me there is a problem with the [/i] with this message this is the message when i search for regsvr32.exe and click it how can i get the code to work so i can use the exporter?