The problem... Einsteen had been burried for weeks. I would check on him and he was ok. Then another 2+ weeks went by and I checked on him under the substrate and he appeared stuck in his small shell. He never changed shells when he molted last year. I could only see his pincher and part of one leg and knew he was alive as the pincher would move slightly. I waited a few hours and he never moved or burried again. I found some articles online that said if they don't come out to greet you they are either "stuck, sick, or dead". We found some weak spots in his shell and cut out a larger opening. I was afraid he was starving if stuck. I put him in a separate tank and left him with popcorn, food, shells and water. Would come back and the popcorn would be devoured and he would have moved from one area to the next. BUT, if I ever pick him up he won't move or come out of shell. Frozen like a statue! I peeked on him last night and saw his eyes come out and move a bit. My hermies always come out to greet me so I have never seen this before. He is still in his old small shell that was cut open to make a bigger opening. Any advice would be welcome. Don't know why he won't go in a bigger shell. I'm thinking he is sick and needs to build up some strength.
1/31/update:
I put Einstein back into the big tank. Bought some more shells (and pulled out some smaller ones I had from before) and WHALA, this morning he was out of the small one and into a new one. I think the shells I had before where too big and he finally found one he liked! He used to ALWAYS poke his head out when I held him. He has this COOL arrow shape on this back/neck. It's still odd to me that he hides in his shell, but maybe he is stressing or pre-molt. He has molted already within the past 6 months. Thanks for everyones help. I will leave them alone now
. I do keep the tank very humid. Use saran wrap over the screen top to keep the humidity in. I have a heat pad under the substrate under a cave, but don't think that keeps it warm enough. THe temp gage says 65-70. I live in Northern NY so it's chilly right now. I have a heat lamp that I can put on top of the screen top, but won't leave it there when not home and think that could dry them out? I thought I read to use a glass lid? How does air get in?Thanks.
Julie
Can I assume that you have several different shells for him to try? Sometimes they like different styles of shells. Maybe your little guys just does not like what is being offered? 
