I love solvespace. It's a wonderful program. But I don't think I've ever been able to make a complete model of something I needed without running into model breaking NURBs errors. Maybe there's a list of known gotchya's that most users know to avoid in their modeling, but for me it seems to break on very trivial things so I've never been able to use solvespace as a tool. Which is sad, because otherwise, I quite like it.