I some time ago i saw similar project on Github, but it only loaded first file on FAT32 partition. I've decided to make bootloader that:
1. Finds first FAT32, bootable partition
2. Searches for specified file(in root directory)
3. Loads and executes it
Another part that is different, is my custom script(made on ubuntu so it's not for windows) which:
1. lets you choose filename that bootloader will search for
2. lets you very easily choose device/partition for bootloader(writes bootsector on specified device - of course leaving MBR ,and sets boot flag on specified partition)
For me, and i think a lot of you guys this is a fast way to just run script, copy your extended loader(or small kernel) on a device and run OS on real hardware
If you want to check it out:
https://github.com/TebexPL/FAT32-Bootsector