For instance, I remixed (but never shared AND deleted) mikeono102's “Home” project, and it showed up on my page.

As well, when there are unshared projects created, it notifies me of them. When I try to access them, they show up as “This project is not shared.”

This is a really stupid bug and must be fixed.

FireNinjaGAME wrote:

For instance, I remixed (but never shared AND deleted) mikeono102's “Home” project, and it showed up on my page.

As well, when there are unshared projects created, it notifies me of them. When I try to access them, they show up as “This project is not shared.”

This is a really stupid bug and must be fixed.

Hmm, so I'm having a hard time understanding exaclty what you mean.
So you started remixing “Home”, then you saw it on your profile (without sharing it?) Or was it in your my stuff? My stuff is private - so it makes sense that it would appear there. But it shouldn't share unless you tell it to.

As to notifications - can you screenshot that? Thanks for reporting!