My K-1s are for Gas & Oil Limited Partnerships. TurboTax seems convinced that they are for Rental Properties and keeps demanding that I enter number of days rented, etc. TurboTax PhoneHelp could not find a way around this.
Form 8949, reporting Capital Gains transactions, provides columns (f) and (g) for adjustments to cost basis, but you must use the OVERRIDE to enter data in these columns and TT error check will not permit that. So you have no place to report Return of Capital adjustments.
What's great about it: Importing, entering & calculating
What's not so great: Mickey-Mouse stuff with K-1s, 8949s