I had a hell of a time getting Sentinel to work on a virtual machine. I finally got it working using VM Ware Fusion. Make sure the VM is isolated from the Mac altogether. Also make sure you are not using any USB sticks while using the VM. Apparently that was my problem with VM Ware
No problem with running Sentinel on Parallels or on VMWare for Mac.
However writing and reading from the Uniden x36 radios in USB mode is problematic.
I use a microsd card reader with my mac to program and update the database with sentinel and write back to the microsd card. This is not a problem with my BCD536HP as access to the microsd card is easy through the front panel.
I never connect my 536 directly to the computer in USB mode as it isn't worth the problems. Uniden's driver for USB mode conflicts with the generic driver used by Parallels and VMWare. Using a separate card reader fixes everything.
I picked up a nice used Dell laptop with Win OS for $120 at my local college disposition store. Not much more than using parallels or a work around, and everything works as it was designed, including the USB ports.
The working firmware is in the scanner, not on the SD card.
During the process of upgrading the firmware, the firmware file is downloaded to the SD card briefly through Sentinel, and as soon as the scanner re-boots the new firmware is loaded into the scanner from the SD card and the firmware file is then automatically deleted from the SD card.
I use Sentinel on my 27" iMAC in a VirtualBox Windows XP virtual machine. I also use the PSR-800 EZ Scan software as well as the Uniden BC125AT software in the XP virtual machine on the MAC. All works fine. VirtualBox even supports USB2.0 in addition to USB1.1 with the VirtualBox extension pack.