Modify registry without HID device

I am working on a program that will not allow plugging in new USB HID devices but will allow devices like cameras, memory sticks etc. I have accomplished what I need with simple registry entries. Everything was working fine until the system got locked down because, for any reason, HID devices coected to the system were uninstalled.

In this scenario I have working Windows system but it is not possible to coect any HID device to it. There are no other ports than USB. I caot even use system recovery because it is available only by:

• restarting system with SHIFT held down (no keyboard)
• failing to start windows 3 times in a row (system boots up fine)
• using control panel (caot get there without HID device, I guess)

So what are my options to get back from this scenario to working system without having to reinstall Windows? Maybe there is something that I can do before the scenario happens to be prepared for this case?

Also (as stated in the question title) it would solve my case if I could modify registry.