The next step would be to upgrade the system to Debian testing, and then check again. If it still doesn't work, upgrade to Debian Sid, and then check again.
If it worked on any of those, report that and everybody knows in what version the issues will be fixed. If it doesn't work in any of those, go over your marketing and remove claims about linux compatibility. The engineering side of this is less than one work day of one developer. It's literally installing, compiling, starting, upgrading, compiling, starting, upgrading, compiling, starting.
The next step is to figure out in what component an error is, and get the latest upstream version of that component. Then, if the problem still persists, file a bug report against upstream, not against Debian. At that point, you are mostly done, and can at least claim to having done your part.
This isn't magic, nor is it difficult nor time-consuming. Heck, I would do it for free on some weekend if I were given access.