Well done, Alex. I can add some stuff on empusids in general, size of ooth, hatching time, etc,tomorrow, if you like. Right now, I'll just say something about RH. Your day time RH of 10% is extremely low for just about any insect anywhere. I imagine that you were remembering that Tunisia is a collecting ground for this species, and Tunisia is the home of the Sahara.where the afternoon humidity can be down to 5%. But B. mendica doesn't live in the desert. The northern region in which it lives has between 5-15" rainfall annually depending on the area. The supposed AR for my Yuma is under around 3.6" (I say supposed, because it has been below that for a long time now) and in the afternoons of the driest month the RH will seldom drop below 15% so 20% should be a minimum. Is your house naturally that dry?
In the wild, mantids can suss out the moistest area possible for molting, but that can be much harder to do in a homogenous, controlled environment. I think that such a low humidity may induce bad molts. Another, practical reason for a rather higher humidity is that many elctronic hygrometers won't measure below 10%RH, so you could run into trouble there. O.K. that's it for now.
BRW, didn't we already srart a care sheet on this species with Tammy's pix? No matter,; we can "consolidate" them later!