Code:
 
on *:text:!mmr*:#: {

  var %chan $chan
  var %t1 $read(C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt,1)
  var %t2 $read(C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt,2)

  if ($2 == $null) { msg $chan %t1 | msg $chan %t2 | return }

  if (# == # [ $+ [ $nick ] ]) || ($nick == nillens) { 
    if ($2 == solo) && ($3 == edit) { msg $chan Solo mmr is now $4 | write -l1 C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt Solo: $4 | return }
    if ($2 == party) && ($3 == edit) { msg $chan Party mmr is now $4 | write -l2 C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt Party: $4 | return }
  }

  if ($nick isop #) { 
    if ($2 != solo) && ($2 != party) { msg $chan Specify if you played solo or party. | return }
    elseif ($3 != +) && ($3 != -) { msg $chan Did you go + or -? | return } 
    elseif ($4 !isnum) { msg $chan Sorry, $4 is not a number. | return }  

    elseif ($2 == solo) && ($3 == +) { 
      var %s+ $calc(%t1 + $4)
      write -l1 C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt Solo: %s+
      msg $chan Current solo mmr is: %s+ ( $+ %t1 + $4 $+ )
    }

    elseif ($2 == solo) && ($3 == -) { 
      var %s- $calc(%t1 - $4)
      write -l1 C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt Solo: %s-
      msg $chan Current solo mmr is: %s- ( $+ %t1 - $4 $+ )
    }

    elseif ($2 == party) && ($3 == +) { 
      var %p+ $calc(%t2 + $4)
      write -l2 C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt Party: %p+
      msg $chan Current party mmr is: %p+ ( $+ %t2 + $4 $+ )
    }

    elseif ($2 == party) && ($3 == -) { 
      var %p- $calc(%t2 - $4)
      write -l2 C:\Users\Nillen\Dropbox\BOT\Mmrs\mmrs $+ %chan $+ .txt Party: %p-
      msg $chan Current party mmr is: %p- ( $+ %t2 - $4 $+ )
    }

  }
}


What it does is every time I try to +/- it always go back to 0 like this:
[07:34] <@nillens> !mmr solo - 50
[07:34] <@nillensbot> Current solo mmr is: 0 (Solo: 4103 - 50)
[07:38] <@nillens> !mmr solo + 50
[07:38] <@nillensbot> Current solo mmr is: 0 (Solo: 0 + 50)


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Nillen @ irc.rizon.net