If you switch to a paid account and then redo the icon import, it will import your icons correctly. However, it will not yet attach them to the old entries properly. I believe someone is working on fixing this, as a lot of people have had this problem.

If you get a paid account and then switch to an unpaid account, the icons become "inactive" but are still there, so if you switch back to paid later, you can still use them.

I'm not sure about your other questions so will leave that to someone else.