All previously forged item revert back to their "heated" state after saving, exiting, and restarting the game. This also dismantles all previously forged item. V 0.0.72
Yes, you are correct. If you scan through some of the other players' posts in this thread you'll see that you're not alone in experiencing this bug. The dev's working on it. If you look under the Updates list on the Trello page HERE you'll see that in the (unreleased) Patch 0.0.73 he's got it fixed. We'll just have to wait until the other issues addressed in that patch are also ready. Thanks!