SVG - Help!!!!

I am hoping to work on some animation using Scratch but I can't stand the few options offered in their Library of sprites.

We have been using png files to code but to animate I need vector files that I can "break apart/ungroup" with the kids.

All my attempts have been unsuccessful.

I have downloaded files which end up on Illustrator but when I save them as svg files they became one big black blob when imported into Scratch.

 

Do you guys know the secret?

Am I importing the wrong files?

Is there a different software to help make it compatible?

 

Thanks and have a great day!