You folks that are having BIOS size errors ... look at the file size of the .BIN file.
If it is 131.072 bytes, it is a 128k binary, and needs a 256k bank.
If it is 262,144 bytes, it is a 256k binary, and needs a 256k bank.
If it is 393,216 bytes, it is a 384k binary, and needs a 512k bank.
If it is 524,288 bytes, it is a 512k binary, and needs a 512k bank.
If it is between 524,288 and 1,048,576 bytes, it needs a 1M bank.
In your Xenium OS, make sure you have your bank arrangement set up to properly hold your BIOS.
Example: Xenium defaults to 4 banks of 256k. If you are trying to install the Xecuter BIOS with the FTP server, you need a 512k bank, so you will have to reconfigure the bank modes to give you 2x256 + 1x512. You would then flash your 512k BIOS to bank 3. Make sure your default BIOS is then pointing to either Original BIOS or Bank 3. If not, you will get a frag on reboot, because the box is trying to load a BIOS from a different bank (eg. Bank 1), which is blank.