Thickness must be <1mm, otherwise the capacitive touch wont register anymore.
I don't understand. Presumably you are gluing the non-touch sensor side to the wood?
It would also be good to understand why screws aren't an option and what kind of wood. Are you gluing to a thin piece of plywood with a cutout for a down-facing sensor?
Anyway, my first choice would also be standard long-set epoxy. Hot glue is tricky because it doesn't stay liquid very long so it is hard to get a thin and uniform layer inside the bond. You would probably have to make do with a few spots around the edge. Epoxy on the other hand gives you ample time to position the work pieces, secure them, clean up squeeze out and so on. Watch out for flow. Epoxy has a gotcha that if you use heat to cure it gets substantially less viscous when first heated. This helps it form a good bond as it flows into narrower areas and can permeate the wood fibers a bit more, but it can also flow where you don't want it.
Hot glue is a quick and dirty option, and it might work OK. It has the advantage that you can hold it in place while it sets, and it doesn't become less viscous at any point.