I would suggest that you request to have this thread moved to the Tennessee Forum. There, you would be more likely to find someone relatively local to you that could help you get a working SD card in place. If you can find someone in the area, and could mail him (or her) your current card (or a new one), they would likely be able to easily create a new programming file by appending systems from the main database. That is basically what ScannerMaster & the other dealers that promote 'programming service' do.
I don't own a Mac, so can't advise you on what steps you need to take to get the Mac to correctly handle Sentinel & programming a card.
I realize that, if possible, you want to use your existing Mac. However, ideally, your best move would be to get a Windows machine, laptop or or desktop, and handle your programming with it. Look at this r
ecent thread discussing sources for cheap laptops to be used for programming. As noted in that thread, Sentinel does not require a lot of PC horsepower to run. It does not need the latest, greatest, and fastest processor, nor does it require large amounts of memory. You would, of course, need one capable of connecting to the internet, so that you could maintain the database in Sentinel for both your SDS200 and the HP2 (if you still have it).