Can different Gen versions of the .NET Proxies be deployed on same machine?
As long as the proxies (and applications) are in different directories and the directory is in its own silo, then it should work.
For example, the following example is is OK.
C:\Apps\App85 and C:\Apps\App86
The following example not OK since the 86 directory is not in a different silo from the 85. There is no guarantee which commcfg.properties (and maybe others) will get picked up and used.
C:\Apps\App85 and C:\Apps\App80\App86