Is Reverse Boss Order, just the 5 main bosses? Am I allowed to kill the Arachnid Queen first for the jump boots? Or do I need to beat the factory before getting the jump boots?

Hello, is there any news about new games from this game developer or it died afterwards?

So many door gimmicks, so many keys to locked doors I'm almost at the point of quitting the game. I have three gems(?) yellow, green, and purple Iris told me I should take the elevator to the highway?? But I've already been there and can't go anywhere, blocked by pillars. Where is the next destination??...

So I have 1 simple key, and can buy one more from Sly in Dirtmouth. I just finished the Hornet Cutscene in The City of Tears revealing some final boss area. When I want to continue through The City of Tears I need a simple key. But I wonder if there is a somewhat important lock afterwards that needs the one from Sly. I heard that you can always go around in this game whne you don't have keys, but I don't really want to make it that difficult for myself. So do I need to keep 1 key just in case? Cause other...

I usually play on two PC and cloud save synchronization helps me a lot. Will you add this functionality?