Boot Mode 1 is for majority Mac machines.
Boot Mode 2 is for certain model Mac machines, such as: certain first generation MacBook Pro.
If you are running the VR as your operating system drive on the 1st generation MacBookPro, and you are having problem to start up the operating system. You should change to the VR / VRMini to Boot mode 2.
Please keep in mind that BootMode2 is only applies to certain Mac machines. We suggest to try the BootMode1 first.