WhiteMagic

This definitely sounds like something is going wrong, as nothing Gremlin does really is computationally expensive. You can find a log in %userprofile%/Joystick Gremlin/system.log One possible source could be that...

By the sound of things it's not an issue with vJoy devices being lost, or at least not severe enough for log entries. One thing you could try to see...

Are you by chance using a Macro inside the long press and triggering the action at a high rate? Someone else recently found that this combination can cause this issue....

Hm that's a different scneario then. In the binding nothing is very out of the ordinary, only that cycle modes with one mode is kind of redundant.