this might be due to the overlay handler.
1) please tell me what version you have installed.
2) install the latest version, 3.0.47, which has an optimization in the overlay handler. After installing, restart explorer.exe manually (sometimes the installer fails to do that) or reboot the machine.
3) if the problem persists with tabbles 3.0.47:
3.A) send log_overlay_handler1.txt to bugs AT tabbles.net
3.B) try disabling the overlay handler (menu > options > disable explorer overlay icons) , restart explorer.exe or reboot the machine, and tell me if the problem is still present.