Sorry guys, checked the FAQ's but cant find anything relevant.

Finished the shoot em in the head quest and Crowley went off on his quest to get the T51 armour. Haven't seen him since..
Remind me of the code to find him someone!

Cheers.

moveto player 0002b8e0

Yeah, this happened to me a few days ago. I wanted to follow him far away from Underworld to perform his execution, but he just disappeared. I tried waiting outside Fort Constantine for days, but to no avail.

Eventually, I just loaded up a save. I hope you have a spare, too, or you risk never obtaining T-51b.

Thanks guys, appreciate it.
Hopefully wont have to reload, have done quite a bit since then!

Ah, well then always be sure to keep multiple saves. You never know when something might go completely wrong, anf you won't want to make 5 hours of gameplay go to waste.