Issue with navigation using custom buttons and Random Question Draws

Hi guys,

I'm working a complex build in Storyline 2 and having an issue regarding navigation from a Random Question Draw. I have created a button (that sits on each question slide in the Question Bank) that jumps to the next slide, so when the user has reached the last of the randomly drawn questions, this will navigate to the results slide (which follows the Question Draw). I created this setup as a prototype without content to ensure the functionality would work as desired and it was fine. However once I built the rest of the project and tested, I reached the final random question in that Draw, and the next button is active (responding to hover) but will not function. I can't use the player buttons as this requires a customised button on the slide itself.

Unfortunately this is a client project so I cannot upload the files publicly, and I have been talking with Articulate support to resolve this but haven't had much luck. I am working on stripping the project down to leave only the functionality so I can post it here, but has anyone tried something similar or know of a common mistake with navigation and question draws that I might be making here?