Workflow for HDV to SD delivery

I will be editing a program in Cs5.5 on a PC. Footage supplied is in PAL HDV formats that is upper field m2t and mpeg from a Sony HDV camera and Canon DSLR respectively.There is also - progressive mp4 footage from three gopros. Delivery format is SD. Very concerned about clip jitter on air. What would be the best workflow to employ and deliver to SD without going the DV format route. I do have a decklink HD card but it is a legacy card which does not fully work on 64bit machines - I can export to Black Magic uncompressed but the broadcaster would not be able to import the file without loading the codec which they will not do. Broadcaster is dominated by AVID systems. Advice much appreciated.