I cubed and roasted butternut squash dressing it very lightly with s&p and evoo. it came out a little too salty and dry. How to correct?

physically wipe off the salt.
le bec fin

To balance the salt, add EITHER acid or cream/fat.
For the first, lemon or lime juice, or quality vinegar.
For the latter, butter, cream, cream cheese or some mild rich cheese.
The dairy will also help with the dryness.
If you go for acid, add some olive oil or other cold-pressed good oil. And maybe serve it cold as a salad.