My first VSO was a clip for this garnish/trim for some blinds my mom had. Due to the way the blinds fit in this specific window, my mom couldn’t use the factory hardware to fix the garnish to the blinds, so for the longest time she was using adhesives which would fail over time. One day (shortly before my printer arrived) the garnish fell again and almost hit my cat, my mom expressed frustration over it, and over how she would have to go by more adhesives. I reminded her that I’m getting a printer, I could just make something that would mount it permanently.
My second one was two mounts for my IKEA lack enclosure. I wanted to make a Nevermore filter, so I needed a power supply. Thanks to working at an electronics lab, I managed to score the power supply from a server rack PC. It’s absolute overkill for this, but it came out looking pretty clean, even modeled in a mounting hole for a simple toggle switch so I can activate the power supply without having to plug/unplug the unit.
Had this happen as well with the GR86 trunk handle file that’s on there as well. I made a make, tried to mark it as such, but was given the same error. Like with your case, the creator doesn’t have an option for purchase/support.