no real need to set any vars for this. look into using $awaytime and $awaymsg
also you should really add some kind of flood control to ur on text/action events or risk being flooded off.

here is an example without vars

alias away2 {
  ame 14,1is now 11away 0,1- 14Left at11 $time(h:nn tt) 14with the reason0,1:11 $$1-
  tnick $+($me,[aFK])
  .away $$1-
}
alias back2 {
  ame 14,1is now 11back 14from0:11 $awaymsg 0- 14 $+ $me was gone for0:11 $duration($awaytime)
  nick $mnick
  .away
}

or make it one alias

alias away2 {
  if (!$away) {
    ame 14,1is now 11away 0,1- 14Left at11 $time(h:nn tt) 14with the reason0,1:11 $$1-
    tnick $+($me,[aFK])
    .away $$1-
  }
  else {
    ame 14,1is now 11back 14from0:11 $awaymsg 0- 14 $+ $me was gone for0:11 $duration($awaytime)
    nick $mnick
    .away
  }
}

just to give you an idea i guess