Seriously Adobe? You release CS 5.5 May 2011 and InDesign CS5 plugins seem to load just fine, but then just last week, you release an update to InDesign, and under Resolved Issues you list: “CS5 plug-ins can be loaded in CS5.5, leading to code conflicts and instability [2867833]”, translated: “Every plugin you thought worked in CS 5.5, doesn’t really, so we aren’t allowing them to load anymore.”
Boo.
You suck.