.TIVO with CAPTIONS on Mac

How can I save a high quality .TIVO file to my Mac that can be later uploaded to the Tivo Roamio Plus preserving Closed Captions?



I have cTivo, kmttg, pytivo and would buy Tivo Desktop to run in Windows 7 under Parallels if that works best.



I just want the best quality .TIVO file on my computer hard disk to put back to the TIVO with closed captions. Then I'll be ecstatic!



If Tivo Desktop does that and runs on a Mac in Parallels then I'll buy it.



Thanks much,

-deac