And have now added the final touch to the loader, it decompiles the code image and makes sure the emergency bootloader-shunt will always be honored in any code to be uploaded.
It is extremely finicky, whatever image is compiled must be opcode-for-opcode identical with what it is expecting. This shouldn't be a problem as long as the code is compiled with exactly the same compiler, already checked that Win32 and linux versions of the compiler produce identical code, I have been asked to do an OSX port of this code but who knows if that is going to happen.
In any case I am still mulling an override button, "really really really don't press yes" and I am currently coming down on the side of no, you may NOT load code the loader does not like, with an on-the-spot explanation as to why you have been dissed, and what steps can be taken to fix the problem. Its just too terrible a thing if unrecoverable code gets pushed onto this board.