Unfortunately, none of the software that covers your 436HP, including Sentinel, will work natively on a Mac. All of the software available requires Windows. You can either use a program such as Parallels to run Windows on your Mac, or find a cheap Windows based laptop or desktop to use for programming. Sentinel & the other programs are not heavy resource users. If you find a used, but functional, laptop it should work. You would also need for it to be able to connect to the internet, in order to maintain the frequency database in Sentinel & the scanner. You might find a suitable laptop at a reasonable price at a pawn or thrift store, estate sale, on eBay, or elsewhere.
Also see: Mac Users of Police Scanner Radios | ScannerMaster.com
If your Mac has the horsepower, running VMWare Fusion or Parallels with a Windows VM, can work quite well. In fact, I'd venture to say that Windows runs more stable in a VM on a Mac.