Mine is working, scanning and displaying properly, Platinum on Win 7 x64.
Have you tried to set prefs to scan on startup and see if they scan through visually at the bottom of the screen?
Maybe even rescan fails etc just to be sure.
I say that because I've seen them hang up in the past.
I may be misunderstanding what you mean by "directly from the folder".... if you mean the preferences, because I didn't see an exe specifically for the manager ... plus I'm super tired. lol
I also assume you meant that after reinstalling x3, it worked momentarily then stopped.
I'm not sure if the manager can open inside or under, like in multidock etc and be hidden, which sounds like a possibility if so.
I have X2, X3, and Plat installed.
Apologies if I misunderstood something, like I say I'm wore out today.. lol
Tell us more about your system, that may help others with an answer as well.