we used BroadcastMessages option to handle the DOCUMENTEVENT_ENABLEDPRE event for setting our v3 license key.
Now we recognize that when onother application with the same wndclass is paused, e.g. because they use WaitForSingleObject(), the broadcast of DOCUMENTEVENT-messages blocks our application.
Only terminating the other paused app will unblock our application.It seems that you use only SendMessage and not SendMessageTimeout to avoid app-blockings
Please consider using SendMessageTimeout to broadcast DOCUMENTEVENT-messages in future releases/updates.
Alternativly you should expand the SendMessagesTo API to set only one special window handle!