That's a good point you made. No, I haven't tested login on as another user .... but I'm pretty sure the symlinks won't be created on the other users' home folder simple because $USER is only identified as the current session and the users running Synaptic.
The scenario is a user installs via Synaptic so the app only gets installed on that user's home folder. And I'm pretty sure that is what I've done.
Now, it would be better if on install time all users on the system including root would get a symlink of their respective folder.
Thanks for the tip, TerryN. It might be just the %post I am looking for. I opted for symlink so I don't have to copy recursive folders and files.
INP1 ... did you just come up with that?