If I install VPX 17 on the machine where I have VPX 16 installed, will it be replaced? Or is it possible to keep both versions installed? (In this case, does the v17 installer offer an installation location?)
Normally the new version will uninstall the old version but any third party effects that still have a current licence should remain. Sometimes opening an old project in a new version makes it impossible to open that project in the version it was created in if some alterations are made in the new version. So use a copy of the project if not certain or give it a new name when saving so you can open the project in an old version again minus any alterations you may have made in the new version.