I can answer the first one.

1: Get to your user page (whether it's by clicking on your username in this forum or by clicking on 'Hello, LowSociety' in the top right of your window.)

2: Look just above the art you've submitted, and you'll see words that say (starting from left to right,) View, Collections, Comments, Edit, Followers, Friends, My Downloads(if you have those enabled), OpenID Identities, Points, and Favorites. Click on Edit.

3: This will allow you to edit all your user information, such as your username, email, password, signature, and profile picture. This should take you to a page where you see those things in that order, from top to bottom. In the picture section, which is just beneath the signature section, you should see Choose File. 

4: You can either drag and drop whatever image you want onto Choose File, or click on it to choose a file from your computer.

5: Scroll all the way to the bottom of the page, and click save.

That's all there is to it!

Can you bump CC0 Remakes? I've added quite a few things since I first submitted it. 

Can you repost the link? I can get to your songs on the main page, but through here it says your submission cannot be found.

Several at 9:33 A.M., in my timezone.