I'm using this extension on a wizard. I need 2 fields, Principal Investigator, and Co-Investigators. both work from the same ds, and no item can appear in both fields. Superbox select is perfect for this since it removes items from the store.

A few things i want to achieve:
-Principal Investigator should be single select, and for the most part look like a standard combo except for ability to delete selection
-Co-Investigators should be a set height, and once the items exceed the height it the box should be scrollable instead of growing

How can i achieve this. thanks