Hey there @LionInABox! First I’d recommend reviewing the logs from the development build, if there are any errors they could provide some insight into the issue.
Next, set up a default button that does something simple, like changes color on click. Is the input accepted?
I haven’t used PNC myself, but it seems it comes with it’s own setup for mouse input, which could be the root of the problem. The button test above should help discern if that’s the case however.