i thought is was more of an on board colostomy bag deal that he emptied in his chamber. as for his genitles, if you look at him being put together his pants around the pelvis dont seem to have taken as much damage as most other places so id say they survived. possibly not in full working order though from heat damage.
i think he could swim, though not well. his suit is supposed to be sealed and he survived in space with it in a tie, which has no life support at all so water wont damage ant electronics. hes too heavy to be fast though, his limbs would weight him down enough, probably a slow dog paddle or breast stroke is all he could manage.
his control board is probably water resistant, its too much of a weakness not to be, all the rebels would need to do is hit the fire alarm and set off the sprinklers and it would take him out otherwise. after an extended period submerged it might take some damage though.