Once I've decided on the best way(s) to link schemas to documents, I need to implement this in code, in the TIMTDocument object, so the correct schema links are added to the files when they're saved, and preserved when they're opened. The latter might be much harder than the former, because if they're PIs they're not so accessible through the DOM...

Once this is done, we need to test the automatic conversion code (XSLT) which runs when opening a 1.4 file.