I am trying to add an aggregation relation from 'Property' -> 'ConsumerPropertySelected' object, but it wont add any type of relation. (See the image)
If I invert the direction ('ConsumerPropertySelection' -> Property) then it adds a relation but the aggregation diamond is pointing in the wrong direction
(Currenlty I pick the relation from the toolbar and drag it between 2 objects, which worked for all the other relations... Not sure if there is a different way to do it or some setting I am missing)
This looks like a bug, however there is a workaround.
If it doesn't work the first time, try it again and it should create it... Hopefully this bug will get fixed soon
EDIT: Looks like the bug is fixed: https://cgit.kde.org/umbrello.git/commit/?id=42d5073216f6801fef68dd6a4508b9a0e1f67ef1 The fix will probably be deployed with the next release