I’m sry, my english is not so well.
I ment with the difficult of the entering the things you saied. So the touchscreen and the password with failures by the entering. It’s NOT a user problem, that the user don’t no how to do this.
A usb-stick is in my opppenion one way to make it faster to lock and unlock the surface. If there are any other solutions for the problem, it’s ok for me, of course. The usb-stick is just one suggestion i know from some pc-systems (like software dongels etc.). My problem is just that the entering of the password on the touchscreen takes to much time – even when you often need to lock the surface. In some bigger locations thats no problem because the FOH-place is seperated from the people. But i have often situations where thats not.