Now, that said, the way you debug your submittal is to paste an entire page of error gibberish that looks like very low level database error output into an entry box they point you to. Sounds gross! Ewwwww! Well actually I've been debugging c++ templates since forever and hohum it doesn't bother me. However... every single time it decoded the problem and told me exactly what I needed to do. It has taken me 2-4 tries each year to get it debugged and then it sails right through. The final result I've fed into two different state forms and that has sailed right through too. All free, and not that much of my time.
Now if they can get the UI for normies painless, which I suspect is the main programming problem (I don't say that UI programming is trivial), this will take off like a rocket ship and the US can the join the coterie of civilized nations that do this for all their citizens.