Another interesting test on my end. There are no such characters in my file. Perhaps our friends at google mail added them :D. The nano editor purports to convert MS-DOS style files automatically when they are opened unless you tell it not to. I have long used that editor to do just that.
In any case, the actual error involved here is in a function called get_fbb_port() in the fbb script. It has no reference to the axports file whatsoever, so I am a bit confused as to why said characters are an issue? The scripts propmts the user for the name of the first port in the file and collects the answer into a variable REP. If the user enters a <CR> then it breaks out of the loop and writes a default port.sys file. If the user does answer, it writes REP to the NUMPORT'th value in the PORT_NAME array. That's where the error occurs. Why is this related to the axports file?
from fbb:
# declare -a gives sometime problems... # declare -a PORT_NAME NB_CH PORT_FREQ
Perhaps PORT_NAME[] is undeclared? and this causes the error?