Ok, been messing with it some more. I know everyone's workflow is a little different, but in practice you really only need 1 2-slash eighth note in the Idea window and 1 3-slash quarter note. This is because after pasting into your score, you can change it to other values and it still plays back correctly!
8th note converts to dotted 8th just fine
Quarter note converts to dotted quarter, half, dotted half, and whole just fine!