Each time I click on the button "OpenTopoMap" CaveRenderPro freeze.
Then I need to reboot my computer.

same kind of issue here but it's not as bad as total freezing and PC reboot. When I go to OpenTopoMap view, it takes some times to get the cave displayed (with graphical scale and OTM license comments) but no OTM tiles are uploaded. Then CRP seems to freeze, but if I click on Plan view, after a while, CRP actually goes to Plan view. So CRP doesn't seem to be completely frozen at this stage. However, CRP gets sluggish as hell and pretty much nothing can be done at this point but to close and relaunch CRP.