That black screen with game capture is that OBS needs a fixing to detect that game, however you could try testing running OBS as an Administrator and then testing game capture to see if its shown(also test enabling in game capture options, anti-cheat compatibility hooking). Test both 32 bits OBS and 64 bits OBS just in case if only on one of them it works capturing it. If nothing then report it as a bug, of not detecting Arma 2 through Game Capture.I tried game capture without the Elgato, but all I get is a black screen then (I'm trying to stream an ARMA 2 mod, maybe that's the black screen problem).