We have been working with dtregister for over a week with varying success.
My problems began when I upgraded to 2.7.3 from 2.7.2e. I can't create events with or without repeats. I was able to do this with 2.7.2e. I can see the events from 2.7.2e when I am running 2.7.3. I submitted a ticket on this issue.
However, at this point, I have decided to postpone using dtregister and revert to jevents at least for now. Jevents was simple but functional and I have used it for several years on my site.
I saw other problems with 2.7.3 too. JURI::root() wasn't used when redirecting joomla.javascript.js in administrator in a couple of files causing errors in the ssl log . Also, I browsed the database with phpMyAdmin and noticed that repeat information lingered there even after deleting repeating events.
It is certainly possible that these issues could be due to an initial problem in our site, either in configuration or initial install of dtregister.
You didn't really say why the event couldn't be created. As in what happens when you try to create an event.
We had a problem when using the JEvents Sync where DT Register was looking for a 12-hour time slot, and the JEvents was feeding 24-hour information. It was locking up and couldn't create the events.
I had the same problem after upgrading. I tried to create events but when I hit apply or save nothing would happen or all the fields would go blank. I decided to to a fresh install :
I uninstalled dt register ad cleared the database of all the dt register tables. The problem was solved. I hope this can help you.
I hear your pain. But I could do it because the website hasn't been launched yet. I'm nervous though as my client will be unhappy if the component turns out to be buggy.
One thing you could try is to back-up only the tables that store events information and delete the others. Hopefully the problem will be in one of the erased tables.