H.A.F.
a.k.a. Rusty Nails
If it doesn't have vents you can rig something, or even gradually prop the lid up at the bottom. The trick (I think) is the gradual hardening off to get them acclimatized. You'll turn off the humidifier at some point correct?I have one I bought for sticking clones in. But as soon as they outgrow that in a week they would have been shocked from high RH to about 20% RH.