shows all submissions?

No, but you can build a view using the Views module that filters down the list to only show submissions by group users. I don't plan on making the functionality you've described part of this module.

sSrry to resurrect this thread, would you be able to give me some advice on how to create this view quickstrech?

I have one webform that is accessible from all groups on my site, however I only want group administrators to be able to see results from their group members. Currently group admins can see webform results from all members in all groups.

I tried creating this view, but think I'm getting confused with what relationships and filters I need, if you could help I'd really appreciate it, also with the best place to put the view.

Many thanks.