I'm not personally going to invest time in back porting the code to 8.5.3, but I understand that this could have value for many developers. I don't believe that the code is that far off 8.5.3, so if someone is interested in doing the work, feel free. We can create an 8.5.3 branch on GitHub.
Just curious: it, for sure, requires the Extension Library or UP1. Do you have that installed? If so, what kind of error did you get? Designer or Server?