Ok, so now would be a great time to add an undo zone feature. For example, I move a large group of units, we'll call them A. Then I move large group B somewhere else, then large group C. I later decide I want to change what I'm doing with group A. Current choices to undo them are to right click and undo each individual unit in A, or to undo the whole turn and have to remove B and C that I've already done. Both are a PITA.

So a 3rd option, like right clicking in a land or sea zone and being able to "undo all units moved into this zone" would be awesome.

Good suggestion, but will need to wait for new client for this one.

I'm not sure if this is the same phenomenon but I couldn't find a way to take back a seaborne invasion - once those units were transferred from ship to land I couldn't take back the action. Other movements I could take back.

There is a current bug that prevents the right click undo option from consistently working but it only affects transports. Right now, if the problem presents (which it does not always), the only work around is to click the Undo button but this means that you must also undo all the moves made between when the transports were loaded and/or moved and when you decide to undo them. In cases where there are large numbers of units that have been moved or specific flight patterns with a lot of aircraft that want to be maintained I have found that it is often easier to start from scratch.

This is a known bug that Admin is currently trying to fix.