Paratext 8 should normally lock the project at the beginning of the
send/receive for that project and unlock it at the end, so you should never
get a locked message if you did a successful send/receive.
I don’t see any automatic reports from you, so please send a problem report
so we can see if there are any clues in the log about why the project would
have remained locked.
We put an upper limit of 30 minutes on the project lock so that it will be
considered unlocked after that. Needed to have a fairly long time since a
send/receive on a slower connection may take a while.
John+Wickberg
Paratext Support