Are you sure that account was blocked?
Profile title: "Registered user"
Banned/Suspended is what it says in either of those cases -- which IMHO you didn't qualify for...
Not that there is necessarily a problem with using your own account, rather than sharing one with your husband.
...
Anyway, as Kovid says, just give the conversion some time.
Books with horribly complex markup have been known to take enormous amounts of time, I believe the record is two straight days...
And if you are still having an issue, or it crashes entirely, you can submit the book for debugging purposes on the bugtracker.
It has a "Private bug" setting for just this purpose (bug reports with copyrighted or deeply personal information).
Conversions don't "hang", there are only three statuses really and 67% is where most of the work is done.
Always wait for a crash or a failure, or else assume it is still working.
Using a 64-bit computer with 64-bit calibre and lots of RAM can help things... a lot.