iOS 26.5 Public beta
Tally: 15.0.1 (518) Pro
When updating a Tally in a set using Apple Shortcuts, the colour for the tally is removed and the default colour for the set is used instead. There does not appear to be an option in the Shortcut action (Update Tally) to keep or update the colour although the action info pane seems to imply it should be there.
The colour of the tally is useful, particularly in widgets (including the watch).

