I think this is a design thing more than a bug.
I noticed that group roundness doesn’t apply to Child group or element. You have to adjust the roundness of the element itself, not the group, which renders the function useless on Parent group level.
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A suggestion is to make the Parent group “override” the Child’s setting. Comments?
We decided to let children elements go beyond the group element (users wanted to be able to do creative things there…) so this is by design. On the other hand applying roundness as the children level isn’t too bad).
Aha. Then by design as I suspected. 
Thanks for clearing that up.
I do agree that it should be available on all levels. It’s just easier to let a group override child settings with one click, if that’s wished for. It often takes some more tinkering to get the desired design correct when you have to define settings for more than one element in a group.
I’ll marked this [SOLVED] and change the topic.
