I inadvertantly deleted my Cash account...can I restore just that account from backup? If not, how do I set up a new cash account?
You can't restore an individual account from backup, you have to roll back the entire file.
If you want to add a new Cash account, click the "+" button at the top of the account sidebar & when asked to pick a financial institution select "Offline Account". Then select Cash account for the account type (it's in the lower right quadrant).
Thank You