You should be able to edit the old K-1 worksheet to the new beneficairies info, or add a new K-1 worksheet for an additional beneficiary. 

Once you mark the 1041 as Final, the Cap Gains "should" pass out to the K-1s, if they dont, if you scroll down down down the Sch D, you'll find a table to allocate to the benes rather than the trust.