I've been using FSCaptain with the NGX for quite awhile now and have had no problems. I don't let it do the loading, but rather "simulate" the loading while I manually set the fuel and payload to the specified amounts in the NGX CDU (these are options in FSCaptain to configure). Seems to work fine doing it's own loading also, but I prefer to manually do it. The passenger counts between the NGX's CDU and FSCaptain won't equal out though...manually loaded or otherwise (as long as the weights are good). I could have something misconfigured in the weight stuff as I'm still a relatively new FSCaptain user, but it hasn't affected anything at all...so long as I have 3 green "ready" signals in FSCaptain when I commit, it's all good. Some minor oddities I've noticed, perhaps due to possible misconfiguration on my part, is that I'll get "busted" on airspeed under 10k when it's around 251kts, plus transition altitude callouts in FSCaptain aren't matching up with what's going on in the NGX...the FO's usually very late on the call....long after I've gone to STD per the NGX's indicated altitude. Those are minor quibbles though; it's been going great otherwise.