I'm using the latest version of this plugin: 1.0.8
One majoy downfall of the plugin is the slug creation through the WordPress backend: group organizer.
If not given, it will not automatically create one. And if the group name is copied into the slug field it will use the group name as is. That means:
* slugs with spaces (instead of converting them into hyphens)
* slugs with capital letters (instead converting them all into lower case)
* slugs with umlauts (instead of converting them correctly [ä->ae])
That all could be solved by just letting WordPress handle the slug creation. This should be possible, right?
Best of luck,
PS: Umlaut conversion is usually handled on my website using the plugin "Germanix URL".