Hey Conny,
There was actually much more involved in getting WPML to work with recurring events, and the workarounds hinted at by Geoff there are not recommended:
1. First, because they are complex customizations to make.
2. Next, because they will soon be overwritten anyways by our fast-approaching 4.3 release.
When our 4.3 release comes out—which should be sometime in the first week of October if all goes to plan—recurring events should work well with WPML.
If you don’t want to wait, then head to http://theeventscalendar.com/my-account/downloads and scroll down until you see the “Early Access” downloads. In this section you will find Release Candidates for version 4.3—these are versions that are still being tested for the official release, but they are quite stable and should offer better support for WPML with recurring events than current code.
If you’re interested in the Release Candidates, you will have to download the Release Candidate versions of all plugins that you currently have on your site. Then perform manual updates to use the Release Candidates on your site and hopefully have some better experiences with WPML and recurring events.
Cheers,
George