My Panda Anti Virus reports pico8.exe as a Virus. I can never get it started. Any clue as to why this might be?

Sounds like a false positive, PUP alert, or low rep alert. Can you go into more detail about what your AV says about the program? It would help with identifying what Panda thinks the issue is.

This is what it says:

Virus detected W32/Exploit.gen Location: C:\Program Files (x86)\PICO-8\pico8.exe

I think the heuristic engine sees something in the EXE it thinks is naughty when it starts up.

I got it to work by taking the file out of quarantine and running as administrator. While it was running it flagged it again. I'll see if I can have Panda ignore it.

Since Explloit.gen translates to Generic Exploit you are right in assuming the engine seems to believe it sees some exploit code in the program. There should be a way to ignore and maybe even a way to report a false positive.