Hello I just installed the DT-Register's calendar view but when I try to display events it say "Error in loading data. Retry" and I cannot see any event...
Generally only two things that would cause this type of problem. It's the calendar script being blocked and not able to load:
1) Permissions. Make sure your site permissions are correct... 755 for directories and 644 for files. This starts with your top level Joomla directories like /components.
2) Your template or another plugin is breaking it. Some templates have a "feature" that blocks scripts or replaces scripts (like JQuery) with another version. There are also plugins that do this. Bad idea to use in most cases. If you have some other item going through your site disabling and replacing scripts, then you will have problems.
If you can't find and sort it out, submit a ticket. Thanks.
I had this same problem, thought I would share what helped me fix it...
I determined that sh404sef was the root of the problem. In the sh404 configuration, you can disable URL processing by component.
Configuration>>>By Component>>>DT Register. Change dtregister to skip. Translate URL to "Do Not Translate". And ISO Code to "Do not insert code". Purge the URLs and you should be set.
Works like a charm now (assuming you don't mind your calendar having non-translated urls).