Weird Kayn Interactions

After playing Kayn for only three games and observing others play twice, I've noticed three notable odd interactions

The first is the biggest. His ult. His ult states in the tooltip that his attacks/abilities allow him to cast Umbral Trespass. I noticed that when my Bramble Vest damaged someone, I could R into them. While this would be absolutely phenomenal to have as a normal reaction, it feels completely broken that items can trigger his R.

The second is that when I was transforming in the fountain while at 1/2 health, I was not receiving any healing from the fountain while I was transforming into Rhaast. I assume this is the same when transforming into Assassin Kayn, but I haven't tried that form yet.

Finally and lastly, a teammate of mine stated they couldn't transform at all. He tried restarting client but that didn't help.