There doesn't seem to be any problems with the pack for me. I passed Level 3 after a few tries. I could save more than 50% of the lemmings. On Level 10 I was able to use builders,bashers,bombers and diggers to get through that wall. I could pass the invisible level in the pack. Level 1 has interesting scenery. The "I am A.T" remake is pretty cool. I think this is your best pack I've played.