Does anyone know what this is?
 

This fell out of the top almost into my lap while opening the top. Wondering where it goes and I guess it's probably important or it wouldn't be there?

It goes over the cross bow end just over the drivers head. There is one one both sides of the bow support. They get pushed out of position when you close the top. You need to cover the ends of the front cross bow, it will wear through the top from the inside given enough time. A heavy 2"×4" velcro patch works well. You can pick them up at any Ace hardware store. They come with a very sticky side which holds on the ends of the cross bow.

I'm not very familiar with the parts of the top. Can you point me to a diagram or photo?

Now my top is stuck in the middle position. Won't go up or down. I stopped it to look where this piece that fell out is positioned. Does anyone know how to restart it??

The FSM (link in sig) has a vert section. I haven't looked at it but the other sections have lots of exploded diagrams.

Courtesy Parts has exploded diagrams for most assemblies.