VolvoGirl - thanks for the additional information. That allowed me to progress farther - but I still can't get the correct numbers into the 1040X...
In step 2 - using the Add State button was successful in allowing me to make an edit to the existing Federal return information. The return then showed the total refund amount as the sum of (Original Refund) + (IRS Adjustment for Unemployment) + (newly eligible Retirement Savings Credit).
As Critter-3 had suggested, I indicated that I am a student, which removed the $200 Retirement Savings Credit. The amount shown for the refund now is exactly the Original Refund + IRS Unemployment Adjustment.
So far, all is good. Signed out from Turbo Tax to save all that information, and then signed in again.
The home screen shows only my original refund amount. But I went into the Amend Return function anyway to see what it would show.
When entering Amend Return, the top of the screen briefly shows the Refund amount - it showed Original Refund + Unemployment Adjustment - so I was hopeful that this was going to work. Then it sets the baseline refund amount to $0.
But, once I get into the actual amendment screens and make a change to claim the Retirement Savings Credit, the refund amount jumps to the sum of (IRS Unemployment Adjustment) + (Retirement Savings Credit). So I'm back to square 1.
It appears that Turbo Tax kind of knows that the Unemployment Adjustment has been made already, but loses track of this once I actually make a change in the Amendment.
Unless someone has other suggestions, it looks like I will have to Paper File this amendment.
