ID:2026808
 
Not a bug
BYOND Version:510
Operating System:Windows 8 64-bit
Web Browser:Firefox 44.0
Applies to:Dream Seeker
Status: Not a bug

This is not a bug. It may be an incorrect use of syntax or a limitation in the software. For further discussion on the matter, please consult the BYOND forums.
It just completely ignores it when using KEEP_TOGETHER, not much more to it than that.
Lummox JR resolved issue (Not a bug)
This is intended behavior, and documented. It's impossible to reset those things when they're grouped. You could add an inverse transform, but resetting completely isn't truly doable.
That's incredibly strange, since individual overlays can be transformed however you want. I could just remove the main icon and make it an overlay, but that prevents me from using animate()
Couldn't you use KEEP_APART though?
Not if you need KEEP_TOGETHER
Here's why it works that way: Without KEEP_TOGETHER, overlays inherit transform and can augment it with their own; the RESET_TRANSFORM flag goes back to the identity matrix. To do a full reset within KEEP_TOGETHER, you'd have to keep track of the matrix but never use it until you decided you needed an inverse.

That wouldn't be so bad because you could have a simple flag saying not to use the transform, but what about if it got nested layers deep so you had a KT parent, a normal child, and a RT grandchild? The only way to do that is to track two matrices, and there it gets ugly.