I have been working on a platformer project for a few months now, and it has been stable up to the last release (which I updated to today).
My problem is as follows: I have enemies with a patrol motion based on their touching two invisible boundary blocks (ie Upon overlap with the boundary blocks, the enemies will pause then move the other direction). This way I simply copy and paste the enemy and the boundary blocks wherever I need another instance of it. r90 has broken this, but only some enemies on a given level. What happens now are some of the enemies would simply blow past the boundary and just keep going, while others maintained their normal behaviour.
Furthermore, I have animated sprites pinned onto the enemy blocks (On startup each enemy block spawns a sprite, which are pinned to whatever enemy block it overlaps). The aforementioned broken enemies would not have their sprites pinned and simply leave them behind.
I am somewhat reluctant to upload my capx because it is huge, and I don't want to make it public prior to its completion.
I test my game on Chrome, and am on Windows 7 64-bit. The error (which is, obviously, huge and surprising) occurred after updating to r90.