Not sure I followed all that. You should look at each year and have both those 2 worksheets. They should be in the pdf files. In the Desktop program you can go to Forms and find them in the list in the left column.
You can amend the last 3 years if it will make a difference. Yes you can update the carryover amount. But you have to start from the beginning and refigure each year before doing the next year to bring the right amount forward.
This is from the IRS Pub 550 page 66 Capital Loss Carryover
"When you figure the amount of any capital loss carryover to the next year, you must take the current year's allowable deduction into account, whether or not you claimed it and whether or not you filed a return for the current year. "
Here is pub 550… http://www.irs.gov/pub/irs-pdf/p550.pdf
