I just recently changed it and it really helps out playing as a Minor a lot. A lot more fun now playing as Sweden, Greece, etc.
So Look for this line in the Misc. Text file:
# If Blue Prints can be sold to non-allied countries. 0 = No, 1 = Yes (player could offer BP), 2 = Yes (player could offer and ask for BPs) 0 #0
1 #0
and change it to this:
# If Blue Prints can be sold to non-allied countries. 0 = No, 1 = Yes (player could offer BP), 2 = Yes (player could offer and ask for BPs) 0 #0
2 #0