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@Discouranged:  I've been waiting for my last K-1s to come in before starting this year's return, so can't speak specifically to what may have changed in TT2019.  But I also held BPL last year, so a couple points:

• BPL provided a sales schedule.  They have, in column 4, the amount they believe is your original starting value.  As @Anonymous pointed out, you need to make sure this is accurate, based on whatever value was determined at the time of inheritance.  If this wasn't done right, its probably time for a tax professional to help straighten out that starting point.
• Regardless of how TT handles the entries, you're still doing the math outlined in this thread to figure out the correct Capital Gain/Loss.  You want to do this manually just so you can verify that the right numbers make it to Sched D.  Maybe TT handles it perfectly.  Maybe not.  You'll only know if you figure out the correct values first.  You can also assume the basis on the broker's 1099B is wrong, because they don't have the K-1 adjustments.  
• Even though a couple columns on the sales schedule have changed, the basic logic hasn't:  your total gain/loss is your sales proceeds less your cost basis (cols 3 and 6 on the BPL schedule).  And your total gain/loss is split between Ord Gain (col 7) and Cap Gain/Loss.
• Even though you were forced to exchange BPL for cash, you'd still treat it as a 'complete disposition' in TT.  For tax purposes, that's what it was.  That will also free up your suspended losses to offset the ordinary gain.

Hope that helps to get things started.  I'll know more later in the month when my other K-1s are out.