Code:
alias -l play_alias {
  if $2 isnum {
    var %filename = FILENAME.UNKNOWN.YOU.MUST.ADD.INI
    var %m = 5 | ; set to max [Fserve.N] value if its more than 5
    var %i = 1
    while (%i <= %m) {
      if ($readini(%filename,np,$+(Fserve.,%i),Root.Dir) isin $1) {
        tokenize 32 $remove($1,$v1) $2- To access this file use the trigger $readini(%filename,np,$+(Fserve.,%i),Trigger)
        break
      }
      inc %i
    }
    tokenize 32 $1 $+([10,File:,]) $3- 
  }
  msg $1-
}

* untested, looks right tho *