Skeeter,
I understand your frustration.
I'd first check the connections on the back of the unit.
Make sure they are in tight and not cocked to one side.
You said the unit worked OK after your update.
Under yor menus, I'd double check the following:
Make sure you have the correct transducer selected.
Make sure the fresh/salt water selection is correct.
There is a menu option for daylight savings time, make sure it is set correctly.
Also, it sounds like you may have interference from your main motor or
other electronics on your boat.
Cut everything off except the Sonar and see what happens.
If the screen clears up, then you have electronic interference.
You may have to get a separate battery for your sonar.
Good Luck.