Has anyone completed a VPAT (Voluntary Product Accessibility Template). I sold some software to a university, and they require this form. Any tips would be greatly appreciated.

Nope. But here is it: https://www.itic.org/policy/accessibility/vpat

Is anything special required to conform to the Americans with disabilities act? It seems like this would be a big topic for most Xojo developers. Small companies and individuals cannot afford lawyers and specialist to research these things.

One known gothca is that Listbox is a custom control. Upon testing, I found that it does not show up at all to accessibility devices.