I have only played this newest version. I thought that overall, it is a nifty little demo. I definitely look forward to seeing where this goes.
I agree with others that the soft locking felt a little awkward. I think if you want puzzles that have a lot of soft locking then a rewind system similar to 'Baba is You' would work really nicely. Thinking about something like 'The Talos Principle' I recall the soft locks tended to be really obvious like "oh no I blew up the wrong thing". I think with this demo the soft locks were just kind of like "oh, I guess I am soft locked now".
Esthetically the two things that bothered me were the pipes and the switches. The throwing the magnet into the pipe to open the door mechanic felt very unintuitive. I was stuck for a little bit at the end of the first level. If this is a mechanic you want to keep it may help to have a prompt the first time. More minor thing but I feel like the switch could look more distinct from the button. I tend to think of toggle switches as more lever-y than button-y. That said I understood what to do and this might be more of a personal thing.
For controls I used a keyboard and mouse. I didn't know that I could pick up the magnet by clicking on it because the tutorial said to use 'E'. I would have preferred to play like that had I known. Also I wouldn't mind toggling the magnet with a left click if possible.
For the actual puzzles they felt a lot like a non-lethal 'Limbo' to me. It felt like there was a mechanic and a puzzle together and I had to figure them both out together. I look forward to seeing each mechanics explored in more detail.
A minor bug I noticed was that on the thank you screen the background tiles seemed to be fighting over the layer order.