[... objects in the ui don't move to cursor right away ...] If you click on an object and move off of it fast enough, nothing happens until you move the mouse again, at which point the object snaps to the mouse point. So click, move fast, and _stop_. Wait as long as you like, and nothing will happen. Then jiggle the mouse, just a bit, and the object jumps to the mouse position.
You're right, this is buggy behavior. We have it fixed, but it wasn't included in the release. (It had to do with waiting for a separate Self process that was in charge of getting X events--that process blocks while waiting to receive the next X event, and wouldn't cede control over to the cursor until it woke up by receiving some X event; in this case, a cursor motion event generated by the extra mouse jiggle.)