Best Answer deramor , 09 October 2015 - 20:55
I ended up talking to Installshield support. The Source Location property does work.
This is what I ended up doing:
1. I populated the source location property on one of my components.
2. Installshield created a new directory in the directory table. It called it [GlobalAssemblyCache] and gave it a default identifier NEW_DIRECTORY1 which I later changed.
3. I then modified each other component's source location property to the same value as the the first component. Installshield automatically changed the destination value to the new GAC folder.
The result was that during an administrative install, the components with the modified values were "unzipped" to a folder relative to the msi file of .\GlobalAssemblyCache\<Source Location Value>
So since I modified all my duplicate file names to unzip to a new folder, I can now run the admin install and me left with all the files instead of some getting over written.Go to the full post