No, not at all. Just remember to avoid putting finish on that nut ledge.

So it'sa glue smear. Could be worse. Get some propriety glue remover. Goof Off is the most popular one in Aus, you can get it here on-line, but there are other similar products. Gentle rubbing using that with a soft wire brush (brass bristles) or a hard toothbrush should get rid of it.

The first layer of ply is a bit thicker than normal veneer so will take some sanding, but it's still best to keep that to a minimum.

I wouldn't bother putting glue in that first edge crack at the moment. You'll squeeze some in when you glue the neck on. The neck block is a reasonable size so you'll have lots of body area that is glued to it, so it won't go anywhere. If you do do it now, mask off both sides of the join so you don't get glue on the wood.