The sorting system is new .A few things dont work as intended but they are listening to feedback and fixing it really quickly lately.
1.Double clicking “give” will give all.Holding shift while transferring loot 1 at a time will prevent you from double clicking.
2.You are right about this one.It should only make the items appear that are recognized by the letters you type/the filter you select.
It does it with the recipe on the other side.it should do it with mats as well.
3&4.Item splitting takes some getting used to but it works fine in my opnion.All the options are there and splitting a stack without having a empty slot available can be done by selecting the stack and right clicking on it.When having "heaviest first " enabled the split stacks will reorganize itself automatically and move all the way to the back of your inventory.Yes, this is annoying but simply setting the filter to “no sorting” will prevent this.
- Q is the “loot all” button for chests(because there you are in a menu.) and “F” is the button for looting corpses.Why? If you would press Q while hovering over a corpse you would actually move instead of looting.
Hope this helped. 