When I first looked at one of my project's scripts from scratch 1.4, it would “re-share” it, saying it was uploaded today. This is a minor problem, but it got bad when I tried to remix one of my earlier projects and it DELETED THE ORIGINAL and replaced it with the unfinished version of the sequel! Now the original is completely erased. Scratch needs the ability to “remix” your OWN project instead of automatically deleting the old one.

Note: Sorry if this is confusing, it's a little hard to explain.

You can. See inside your project, then go to File > Save as new copy. This is what I had to do.