This is my first work with dialogs, so it may be a little sketchy;
I used The Freeze MP3 player as a base, and have added on bits and pieces;
Original code found here http://www.hawkee.com/snippet/3255/

It currently only supports playing a single file, and only states the file name and time, but I'm working on it, sorry. =/ I'll update it as often as possible, hopefully it'll get much better. I'm working on figuring out how to add a whole directory, continuous play, etc. Any helpful suggestions would be much appreciated.

menu * { 
  .Torment { Player }
} 
alias Player { 
  /dialog -m player player
} 
dialog Player { 
  title "     [<-TormentMP3->]" 
  size -1 -1 100 130
  option dbu 
  button "Stop", 2, 55 27 32 11, flat multi 
  box "                        Music                       ", 3, 3 1 93 100 
  button "Single", 4, 32 49 37 12, flat multi 
  edit "", 5, 12 11 74 15 
  button "Play", 6, 12 27 35 11, flat multi 
  button "Pause||Resume", 7, 27 38 45 11, flat multi
  button "Say", 8, 36 61 30 11, flat multi
  box "                       Options                    ",9, 3 99 93 25
  check "Repeat",10, 7 107 30 11
} 
on *:DIALOG:player:sclick:4: { 
  //set %file $sfile(%musicdir $+ *.mp3;*.wma*.wav*.wmv*.mpeg,Select music file) 
  did -r $dname 5 
  did -a $dname 5 $regsubex($nopath(%file),/\.[^.]+$/,) 
} 
on *:DIALOG:player:sclick:6: { 
  if (%file == $null) { echo -a Sorry $nick $+ , but no file is set to play... }
  else {
    /splay %file 
    set %duration $Replace($Duration($Calc($Sound(%file).length / 1000)),mins, :,$+ secs,$+ ||)
    set %play activated
  }
} 
on *:DIALOG:player:sclick:2: { 
  if (%play == $null) { 
    echo -a There is no song playing, therefore there is no song to stop... 
    halt 
  }
  else { /splay stop | /unset %play }
} 
on *:DIALOG:player:sclick:7: { 
  if (%pause == $null) && (%play == activated) { 
    splay pause 
    set %pause activated 
    halt 
  } 
  elseif (%pause == activated) { 
    splay resume 
    unset %pause 
  } 
  elseif (%play == $null) { echo -a There is no song playing, therefore there is no song to pause... }

} 
on *:DIALOG:player:sclick:8: { 
  if (%play == $null) { echo -a $nick $+ , there is no song playing... }
  else { describe $active  is currently listening to: $regsubex($nopath(%file),/\.[^.]+$/,) $+ || $+ %duration | halt }
}
on *:DIALOG:player:sclick:10: {
  if (%repeat == $null) { set %repeat activated }
  else { unset %repeat }
}
on *:MP3END: {
  if (%repeat == activated) { splay %file }
  else { halt }
}
on *:DIALOG:player:close:0: { /unset %file | /unset %duration | /unset %play | /splay stop | echo -a Torment Player Closed. }