Reason why I ask is that there are many form/survey builders out there, as people often underestimate the complexity it takes to set one up that supports things like max diff, routing etc.

Looking at the forums I can see that some have managed to achieve what you need via plugins (albeit the one I see that is confirmed working seems to be paid…)

Just thinking contributing an open source plugin to a great open source scripting tool would save you headaches down the road :)