Creon 10 seems like a low dose. I was on Pancrease MT4 for the longest time...my doc jumped right past the 12s and put me on 20s, which work much better. So it could be that you need more of the same enzyme or it could be time to try another brand. It may take a little experimenting to figure out what works best, but that's where I'd start, especially since you a)can't have a ton of sugar due to the diabetes and b) already eat a ton (so calories aren't the problem).
Also, if you are stressed or anxious about this, have you thought about trying an anti-anxiety med to help get you through this period? It sounds like you are saying if you could just calm your mind, gaining would be easier.
Good luck - please keep us posted on what you decide. <img src="i/expressions/face-icon-small-smile.gif" border="0">