I agree that this icon is confusing. Rather than recognising which state the icon is in, it's more of a case of if my group is not suspended then I need to press the button to make it suspended.
This begs the question, should you suspend just one group that your working on, or suspend groups globally? Like Adobe Illustrator introduced into CS2 I think it was, where double clicking a group, opens that group in place - effectively suspending the group. Whilst I don't think this implemention would necessarily work in AC, would a contextually aware suspend button in the pet palette be useful?
Therefore, if I have selected a group, suspend appears in the pet palette. If I select an element that is in a suspended group, un-suspend appears in the pet palette. If I select an element that is not attached to a group, then there is no suspend button in its pet palette. This I guess follows on from what Ben was saying about buttons being more aware.
James Badcock
Graphisoft Senior Product Manager