P3 ATC won't activate?

Has anybody tried using P3 with FS2020? I have it installed on my PC (I know it’s an older ATC addon but I want to try it out). It is supposedly a free program now. However, when I try to run it I get a window for an activation code. The download from their site said to use an activation code or “999”. So I am using 999 since their was no activation code sent (and it’s free so I assume that’s why). Anyway, after entering my activation infor the window just closes and the program never starts.

Did you download and install the runtime libraries from their site…and I reckon you mean PF3.

I think it was not installing it as “Administrator”. I’ts good now.

Actually, it isn’t. I can start the Demo version, but the full program still asks for an activation code and then tells me activation failed.
The demo version doesn’t ask anything- it just launches correctly. Frustrating.