Hi @mathamtix,
I’m very sorry for how long this ticket has been sitting here – since you were not the original author of this ticket, I didn’t realize this ticket had been updated!
The bad news is that since the specifics of this microformat are dictated by the markup of your pages and templates, the only way to fix these issues would be to either customize Events templates directly, or make new ones as laid out in our Themer’s Guide → http://tri.be/support/documentation/events-calendar-themers-guide/
The good news is that these hAtom “errors” cause little problem anywhere outside of Google’s Webmaster tools.
Let me know if you have any thoughts on this, and again: I’m very sorry for how long this issue has stagnated here.
Cheers,
George