Chase Plane works fine with P3Dv4 and FSX.SE but will not work with FSX. The option for it to start with FSX is grayed out. Tried editing the registry with VFXCentral and it's grayed out there too. My path to FSX is extremely simple. C:/FS. Do I need to put anything else in the registry editor and if so how? Using beta 0.3.70. Saw others with some version 4.something or other. What is the latest version? Thanks in advance.

I would first try the Flight1 Registry Repair Tool to validate there are no path issues.  As for versions, it sounds like you're using the stable version, 0.4.xx refers to the experimental version.

BTW, I use FSX with Windows 7 Pro 64-bit without issues.. well, mostly. 

Ernie