It’s kind of a problem for me because automation isn’t really stable, and once it didn’t let me put an engine in, so why can’t we save platforms anymore?
It was an interim change to allow work on a revised solution.
I’ll probably put out a new youtube video tomorrow showing how they come back, like maffc says it was a temporary thing that allowed us to release an in-between version. Platforms and Models will be saved continuously with the next big update. 
I just lost 2hrs of progress thanks to this removal because the game keeps crashing.
As an interim workround, start a new model, set a platform layout, add a body, a saved engine and use any settings and save. should take about a min.
Then you can tweak and save as often as you see fit.
[quote=“Noporian”]I just lost 2hrs of progress thanks to this removal because the game keeps crashing.
[/quote]
I’d say that’s better than having no new version to play at all for another 3-4 months? 