I'm using a group frame (you can see it below) and want to add a fillcolor. When I'm changing the vlaue from fill color 1 or fill color 2 nothing happend. Why respectivley how can I do so?
Thanks for helping!
There seems to be a misunderstanding here. I did not mean to suggest adding a task activity to the BPMN group, but using a task activity instead of the BPMN group. Task activities (at least those with "+" and "-" signs) are group nodes as well and may contain other nodes as content - see this sample GraphML file.
That said, I think the "auto correction" you mentioned is determined by properties "Top Group Inset", "Left Group Inset", "Bottom Group Inset", and "Right Group Inset" respectively. To change one of these properties, select the group node and enter another value for these properties in the properties view in yEd's lower right corner.
Group nodes have two states: opened and closed. While opened, a group node's content is visible, while closed the group node's content is hidden (indeed it is removed from the current diagram). When you double-click a (opened or closed) group node, yEd will navigate into the group and show only the group's content. In any case, all group specific actions are available in yEd's "Grouping" menu. E.g. if you erroneously navigated into a group, you can use "Grouping" -> "Previous View" to return; if you have closed a group, you can use "Grouping" -> "Open Group" to open it once again; etc.