To the best of my knowledge Toontrack appears to let you run a custom install once and then the install path is hard set in the registry. I can not find any settings in the Toontrack manager to set an install path, only the target download path for product. Arturia have one of the best installation managers as it allows you to set paths for 32 and 64 bit, which is somewhat redundant as they no longer support 32 bit since the V7 collection VST, an installer download path. The VST 3 is always the default for the bit depth of common files.