It may not function out of the packaging without some modification. I ran into this same issue awhile ago when I went to install one of these safeties with a Geissele SSA. The SSA would not function with the BAD-AS$ safety even after messing with it for awhile. Battle Arms Development now somewhat confirms this on their website by saying, "Some fitting may be required with Geissele Triggers on the 50° Short-Throw side." I would recommend you look into a different short throw safety selector. I personally am currently using a Radian Talon safety with my Geissele SSA and Tricon and it functions perfectly.
Yes, the throw levers can be swapped to either side depending on user preference.
Yes, the center safety bar is setup for both a 90 degree and 50 degree throw.
Yes, this should be compatible.
yes, i use pa10 lower. Work great.
Yes, these come with the two different length levers as pictured.
It is a 0-90 degree. It does not a 45 degree center.
Yes this will work with any milspec lower receiver. The 6920 is milspec