I'm upgrading from a Decklink SP to a Decklink Studio and because of the Studio's breakout cable it looks like I am going to have to spend close to $100 for additional cables (my SP's cables all go directly from the card to my equipment) to rewire my suite. I see that B&H sells a replacement breakout cable for a Decklink HD extreme & studio (Mfr # CABLE-BDLKHDEXT) for $119 but I wanted to check in here to first make sure that it would indeed work on my Decklink Studio card and to see if the cable lengths were fairly close to my old DecklinkSP card.
None of those cables are compatible. So, I imagine your issue is that the Decklink Studio cables are shorter than the Decklink SP. Not to mention, the Decklink SP cable was made to connect directly to the back of a deck, and the Decklink Studio was made to connect to patch cables.
This change was made as we had many customers that found the cable on the SP either too short or too long and this allowed them to use simple patch cables (rather than extnesion cables) of any length they wanted.
We do have pinout diagrams available for all of our boards so if you would like to make a custom cable (or have one made for you), just let us know and we can provide that to you. Though realistically it is probably easier to just use a few patch cables (though I don't like having any more junctions than necessary).