This should correct save all the assets required for the items within the coalesced objects in an IAR. This should also correctly gather the items on hypergrid takes.
From pure code inspection, it looks like the uuid gatherer may get most asset uuids because the scene object serializer naively pulls non-root parts from all contained scene objects into one mega-object. However, root part uuids may well still be missing, and there may be other odd artifacts from this bug.
It appears that storing the size of the coalescence and the offsets is redundant, since one can work out this information from the position data already in the scene object groups.
This structure matches the existing one for SceneObjects and will allow code to be reused by the uuid gatherer, other tests, etc.
Test is not yet fully implemented due to a bug in rezzing coalesced objects where they all get the same name as the item.
Only one object should get the same name as the item, which appears to be the one selected last when the the objects were coalesced in the first place.
This bug will be addressed shortly.
Justin Clark-Casey (justincc)