I don't know if this is really a problem worthy of action, but if I've done this once, I've done it 30 times:

1) Load column set

2) Since column sets don't preserve column groups, start grouping columns to re-create correct column layout.

3) Group columns won't  work.  When group command is initiated, the selection is lost and no action is taken.

The first time this happened, I almost posted a thread after spending several minutes trying to get the group command to work.

Then I stumbled on the answer: new column sets have to be saved before the group command can be used.

Despite knowing this, I still try to group columns after loading a new set.

As I said, I don't know if it's worth worrying about.  Maybe an option to save column sets as soon as they're loaded?  For me, saving column sets is an extra manual step that I don't need and I often forget to do.

Wayne