Big thanks for playing the game and I really appreciate the structured review!
1. You can click on a piston to switch directions. But it's never communicated to the player, so thanks for pointing this out!
2. Changing recipe keeps raw materials and destroys intermediates. Fun story: this was actually a last-minute fix as during playtesting my sister has beaten the game with only one factory by only changing recipes (as the factory kept all produced resources). The fix was supposed to nudge players into building many factories but apparently it made you frustrated.
Viewing post in Stellar Constructor jam comments
Ooh yeah okay that makes sense. I didn't realise that saving intermediates would allow you to cheese like that. Yea it was mostly that at the start I had trouble setting up a factory for factories as it required 3 factories (iron, computer chips and one to make the factories) but you only start with 2 factories.
Note: While typing this I opened the game back up and saw that you start with 4 factories. I have no idea how I ended up in a situation where I only had 2 but I guess starting with 4 makes my complaint irrelevant haha.