To enable scroll wheel in text boxes:

*NOTE: This seems to only work within the Player Mission Log window (default key is L), and not the Mission window (when you receive missions from NPCs)*

Within WillowInput.ini:

Search for all instances of the following (there should only be two instances):

InputKeyName="MouseScrollUp",ModifierKeyFlags=42
InputKeyName="MouseScrollDown",ModifierKeyFlags=42

remove the ",ModifierKeyFlags=42" so they look like:

InputKeyName="MouseScrollUp"
InputKeyName="MouseScrollDown"