There are reports of Windows XP users having trouble running the bootloader builder. Also, Linux users are unable to use the builder too. I have a solution
I have pre-built some bootloader files for you, which you can flash via fastboot!
Here are some default sized bootloaders for you:
System: 250 Data: 134
(Default LG partition sizes, needed for Stock 2.1 ROMs and Enigma Soft Mod)
REMEMBER TO NANDROID BACKUP! (YOU WILL NEED TO INSTALL IT LATER)
Download the one you want and put the phone in fastboot mode. Use the following command to flash it:
fastboot flash APPSBL your_file_name.mbn
If your phone sticks at its kernel screen, pull out the battery, put it back in, and then go into recovery. Now, restore your ROM.
If you need any specific partition size, just reply or PM me.
Also, don't forget to say
if I helped!