It's in development, it's just that you can't expect too much from a free program.
There is usually only one major update per year.
To give you a time frame, one year ago I worked out how to make parts from scratch - there are no instructions so I had to reverse engineer them from other parts -, and I complained that there should be a specific place to share parts - they had recently closed the other -, and 1 year latter we got a Part Submit category in the forum. Then they went further and added auto part update.
Even parts take time to come through. I made a part 1 year ago and I was quite surprised that it is now in FZ - I wanted to share it but I didn't expect such an obscure part to be added - , the thing is that I updated it 6 months ago, and that update hasn't come through yet.