I haven't had an issue so far. Though I do use my ha a little different when I do it which I should of probably described.
I wait until it's heated before dropping in the crucible, I inhale slowly at first to give it time to melt in, and I run it at 400. Doing this tends to make the session last a long time too, usually past the first timeout. Also it usually knocks me out and sends me off to a nap.
To be extra careful you can use their crucibles designed for concentrates instead of the regular ones. I actually overloaded a too dirty concentrate crucible once with just wax and it went all the way down and out the air intake on the bottom. Cleaned it with iso q-tips and haven't noticed a difference.
I let the chamber heat up, then I drop the crucible with concentrate (tiny amount goes a long way, the glass beads spread it out for a big increase in surface area) into the chamber and put on the mouthpiece, I wait a minute for the crucible to heat up and the concentrate to melt into the glass beads and screen and then pull on it or fill a bag. You'll get a few bags (Herbalaire single size, I'll be trying the oven bags <double size>) out of one crucible.
It's actually an easy vape to clean, and it's rare for things to 'spill' out of a crucible, but it's stainless steel beneath, so ISO cleans it up pretty easily. I have an extra crucible tube (holds 5-6?) that I use for cleaning, (they sell it specifically for this) I drop a dirty crucible in some 91% ISO (all I can find on a Q&D hunt locally), let it soak for awhile, shake it around, and you've got some fairly dark residue being pulled off the glass beads and crucible into solution. I let them soak for days, as I've got spares of both style of crucibles. I've read some folks try and reclaim this, but have to go re-read how, ISO is not something to make mistakes with for medical patients. I just use a good paper towel that I get wet with ISO and twist it into the chamber, getting as much in there and twisting it around, changing direction, etc.
I get some out of the air inlet, then I blow it dry through the air inlet just with my mouth, let it air out for awhile and then heat it up (with nothing in it) to make sure the ISO has evaporated.
If necessary, I'll use my dental pick to make sure the air vents in the chamber are clear and clean, but that's fairly rare and I use this a LOT.