Previously, someone mentioned that a newer version of the CH340 driver had issues under Windows 10/11 and required uninstalling an earlier version. However, I haven't experienced this issue on my Windows 11 laptop.
Have you checked the COM port number in the CPS software (Settings -> Serial Port Settings -> ensuring that the selected COM* matches what is listed in Device Manager)?
(The issue of not being able to press down on the K button was also very realistic, and I struggled for half an hour before realizing that I didn't have enough strength.)