You get that error because the hash table hasn't been created. mIRC has to see a hash table first before it can load it. To work around that, locate this line:

if !$1  { hload -i c $conf(cfile) | echo *** Config file load }

and change it to:

if !$1  { $iif(!$hget(c),hmake c 100) | hload -i c $conf(cfile) | echo *** Config file load }