Since I was asked about the details of my upcoming fix for the GU30 hotbar deadspace issues for use in another mod, here it is for everybody:
In the main page of your hotbars add the following
OnShow="MinimumSize='0,0'"
In the BankPage add the following:
OnHide="Parent.MinimumSize='0,0'" OnShow="Parent.MinimumSize='0,0'"
I had minimal time to test this but saw no issues. Use at your own risk.
