Ashley, here is a youtube video showing the steps:
As you see in the video, the On start of layout gets incorrectly undone before the other condition.
I also show the same issue with undoing actions.
I create the On start of layout condition.
Then I create another condition that uses an object.
Then I right click that condition and choose replace object, replacing with another object.
Then I undo once to undo the replacement, but then I undo again, and the On start of layout condition is removed instead of the second condition (because replacing the object somehow has now messed up the undo/redo stack).