Important (for me) distinguish VIM from other develop circuit boards that it uses in common with the TV boxes platform. Including the presence of internal eMMC memory, which is the bootloader. From this it follows that it is possible to use a single scheme multi-download. No matter what system you to run from external media - all can be done with a script. Unlike the script for each system in the set of commands that are required specifically for each system. In this case there is no need to erase the bootloader in order to run the system from external media. By the way, the boot loader on an external drive does not need to start the system, from external media during normal operation. The boot loader on external media are needed only if you damaged the bootloader on the eMMC (to restore the bootloader in the internal memory). Here is a patch to enable multi-boot on dualOS. If you think You don’t need it, feel free to delete it.