I was not shown my BAC number at the time it was given. Ten days later I received court papers charging me with DUI. Is this legal?

Yes, that's legal. There doesn't even have to be a BAC test to charge or convict you of DUI.

The officer did a police report, and the Breath Alcohol Content was recorded within the report. The Prosecutor decided to charge. There was probable cause for the stop, because of the cracked windshield.

You can get a copy of the police report at your first appearance in court, at the arraignment. If it isn't given to you, ask the court to give you a copy. The Officer's observations (which support the Officer's opinion that you were impaired) should be in there (red eyes, slurred speech, etc) as well as any erratic driving seen and any test results (field sobriety & breath/blood alcohol).

It is odd that you weren't taken to the station and booked. You should have been given a citation, your car should have been impounded or parked, and you should have been given notice of your driver's license suspension and right to an administrative hearing on your license.