I am running 64-bit SONAR X3 Platinum on Windows 7 64-bit but I want to also have a 32-bit installation for loading files from a previous 32-bit version with DXis such as Dreamstation that will not work in 64 bit. When I install the 32 bit SONAR, it works fine, but when I then run the 64-bit SONAR it won't start. If I then install 64-bit again, it works but 32-bit SONAR stops loading. I have them installed in separate folders, I even tried separate users, but it seems that only the most recently installed version will open at any given times.
Has any one successfully gotten 32-bit and 64-bit installations of X3 to run on the same machine?

I am running x86 LE in x64 along side x1 - splat 64bit without issue for development with no trouble.
As for the same sonar release - don't know.
 

I am not sure if Dream Station will run in a 64-bit Sonar.
 
Bob Bone
 

Ive got the same issue. Splat 32 crashes every time.

Sounds like you need to check which folders the various versions are scanning for plugins.