Re: I'm 155lbs, I want to be 190lbs; read inside.
So, I'm very much new to Crossfit, only about the past few weeks so I'm at scaled workouts right now. But, I know what you are looking for. I'm at 5'11", and down to 210 from 245 (I played football and threw shotput so I needed the mass, hopefully will get down to 195 by January 25th) after a summer of working out and at 13 strict pu right now with 275 max rep bench. Anyways, when it comes to gaining a serious amount of muscle, you're doing the reps wrong in my opinion. I see that you like doing 10-12 reps, and while this is all well and good, if you want to see serious gains in muscle it's going to be all about the one rep max and working towards less reps.
I'd suggest doing pyramids of 10-8-6-4-3-2-1-4 or maybe even tear down, where you throw on 225 for bench (all relative, I'm doing it towards my standards) with 1 45, 1 25, and 2 tens on each side. Then, max out your reps on 225, drop to 205 and max out, and keep doing that till you hit the bar, once you're finished do it all over again for another set with no rest in between changing weight. Up the weight every week that you do it. Also, keep in mind that this is all prior experience and probably isn't in the Crossfit mindset.
I'm not sure what any one thinks of supplements, good or bad. I know creatine works and getting an influx of protein works very well. The kinesiology students here have done studies to show that it hasn't been shown to have bad effects (not sure how true it is, but I'm a trusting kinda guy). Increase the protein, but in the end I always used to eat about 30% junk food. Hoped that helped.