I'm finishing up a Very Hard difficulty playthrough and this update is fixing all the tiny issues I found along the way.
A few gameplay changes were made, but all were minor. Some abilities like Masret's True Strike now lasts 5 rounds instead of 3. Orson's traps last 5 rounds, are a little stronger, and remove other traps on the character so you can't pile them up. Shakar's Sneak Attack is slighly stronger.
Most of the changes were small graphical issues, spelling or other text-based mistakes, or tiny bug fixes.
There's a new enemy in the Vooresh sewers that appears pretty rarely, though you can't get back to that location once you've completed it.
The Void Horror around Virion's Castle is now possible to battle (oops). Go see if you can beat it and get the unique item it gives you!
Enjoy!