If this has already been treated or found, please forgive me.
Cautiously leaving my 2.10 world, I've recently begun checking out all the new features of 2.5. I have to say, I'm impressed. I understand the screenshots look like crap, but I'm just playing around.
I've found that when you use the Quake Hammer attack, it screws up the subscreen like this (note that the arrow counter is cut off):
Then when you warp out with an opening screen, it looks a bit weird:
This bug is immensely easy to replicate, so I've found that posting a test quest was unnecessary.