@dan rathbun said:

_
Sketchup::SelectionObserver

This observer needs fixing! I would put this in the high priority group.

I highly second that request! SelectionObserver is broken.

@dan rathbun said:

Per ThomThom's Observer Review "State of Observers"
http://forums.sketchucation.com/viewtopic.php?f=180&t=20676&start=0#p173630

Sketchup::SelectionObserver

.onSelectionAddednever triggers
.onSelectionRemovednever triggers.

Instead,
.onSelectionBulkChangeand .onSelectionClearedalways triggers.
_

Here even onSelectionCleared is not even triggered. (SU 7.1 (7.1.5803) on MacOS SnowLeaopard) This makes working on selections quite impossible and you can't do that in a right way.

Also, plugins should be loaded before any new model is created in SU. Because AppObservers are not triggered for the initial new model open when lauching sketchup.

Both those issues could be easily fixed. I don't know whether sketchup dev team is reading this forum, but please fix that!

Didier.