first, nice script Zmodem
this should help ya

$isalias(name)
Returns $true if the specified name is an alias command that exists in your aliases or scripts.

Properties: fname, alias

$isalias(join) returns $true if you have an alias for /join
$isalias(join).fname returns the filename in which the alias exists
$isalias(join).alias returns the alias definition for /join

this, if worked in to the script should show the fkeys if pre-existing function keys
exsample: if $isalias(f3) == $true { writeini keys f3 $isalias(f3).alias }
you will have to tweek it to work in your script

enjoy
hope this helps
and yes this is the Whobear from the colorteam.net