So I decided to try my hand at writing the media player code. It uses the nHTML dll... though I'm wondering if I should switch to DCX for this? I mean... I can probably switch to DCX and get a better result... but I'm still learning DCX.

Code:
dialog mmp.dialog {
  title "Video Player"
  icon "C:\Program Files\Windows Media Player\wmplayer.exe"
  size -1 -1 295 235
  box "play", 1, -12 -17 335 269
  menu "File", 2
  item "Open...", 4, 2
  item "Open URL...", 5, 2
  item break, 6, 2
  item "Exit", 7, 2, ok
  menu "View", 8
  item "Playlist", 9, 8
  button "", 10, 0 0 0 0
}
on *:LOAD:{ set %mmp.playdir C:\ }
on *:UNLOAD:{ unset %mmp.* }
on *:DIALOG:mmp.dialog:close:*:{
  if ($dialog(playlist) != $null) {
    dialog -x playlist
  }
}
on *:dialog:mmp.dialog:*:*:{ 
  if ($devent == init) { 
    dll $mmp.dll(mdx) SetMircVersion $version | 
    dll $mmp.dll(mdx) MarkDialog $dname | 
    dll $mmp.dll(mdx) SetControlMDX $dname 10 Positioner size minbox maxbox > $mmp.dll(dialog) 
  } 
  if ($devent == menu) { 
    if ($did == 4) { 
      mmp.open 
    } 
    if ($did == 5) { 
      mmp.openurl 
    } 
    if ($did == 9) {
      vidlist
    }
  }
  if ($devent == sclick) { 
    dll $mmp.dll(mdx) MoveControl $dname 1 * * $calc($dialog($dname).cw + 40) $calc($dialog($dname).ch + 34) 
  } 
}
alias mmp.open { write -c " $+ $scriptdirmmp.html $+ " 
  if (!$isdir(%mmp.playdir)) { 
    set %mmp.playdir C:\ 
  } 
  set %mmp.media $sfile( $+ %mmp.playdir $+ ,Select A Media File To Play,Play) 
  if (%mmp.media) { 
    write " $+ $scriptdirmmp.html $+ " <embed width="100%" height="100%" src=" $+ %mmp.media $+ "> 
    write addons\vidlist.txt %mmp.media
    if ($dialog(playlist)) { loadbuf -ro playlist 1 addons\vidlist.txt }
    dll $mmp.dll(html) attach $dll($mmp.dll(html),find,play) 
    dll $mmp.dll(html) navigate $scriptdirmmp.html 
    set %mmp.playdir $nofile(%mmp.media) 
    dialog -t mmp.dialog $nopath(%mmp.media) - mIRC Media Player 
  } 
}
alias mmp.openurl { 
  write -c " $+ $scriptdirmmp.html $+ " 
  set %mmp.mediaurl $$?"URL To Media File:" 
  if (%mmp.mediaurl) { 
    write " $+ $scriptdirmmp.html $+ " <embed width="100%" height="100%" src=" $+ %mmp.mediaurl $+ "> 
    dll $mmp.dll(html) attach $dll($mmp.dll(html),find,play) 
    dll $mmp.dll(html) navigate $scriptdirmmp.html 
    dialog -t mmp.dialog $nopath(%mmp.mediaurl) - mIRC Media Player 
  } 
}
alias mmp.dll { 
  if ($$1 == mdx) { 
    return " $+ $scriptdirmdx.dll $+ " 
  }  
  if ($$1 == dialog) { 
    return $scriptdirDialog.mdx 
  } 
  if ($$1 == html) { 
    return " $+ $scriptdirnHTMLn_2.95.dll $+ " 
  } 
}
alias mmp { dialog -m $+ $1 mmp.dialog mmp.dialog }
menu status,menubar {
  -
  Video Player
  .$iif($dialog(mmp.dialog),$style(2)) Open on desktop:{ mmp d }
  .$iif($dialog(mmp.dialog),$style(2)) Open inside mIRC:{ mmp }
}
dialog playlist {
  title "Playlist"
  size -1 -1 195 180
  option dbu
  list 1, 2 9 190 153, size vsbar hsbar
  button "Add", 2, 29 164 37 12
  button "Remove", 3, 75 164 37 12
  button "Clear", 4, 121 164 37 12
}
alias vidlist {
  if ($dialog(playlist) != $null) { dialog -v playlist | halt }
  else { dialog -m playlist playlist }
}
on *:DIALOG:playlist:init:*:{
  loadbuf -ro playlist 1 addons\vidlist.txt
  did -z playlist 1 1 3
}
on *:DIALOG:playlist:dclick:*:{
  if ($did == 1) {
    write -c " $+ $scriptdirmmp.html $+ " 
    set %mmp.media $did(playlist,1).seltext
    if (%mmp.media) { 
      write " $+ $scriptdirmmp.html $+ " <embed width="100%" height="100%" src=" $+ %mmp.media $+ "> 
      dll $mmp.dll(html) attach $dll($mmp.dll(html),find,play) 
      dll $mmp.dll(html) navigate $scriptdirmmp.html 
      set %mmp.playdir $nofile(%mmp.media) 
      dialog -t mmp.dialog $nopath(%mmp.media) - mIRC Media Player 
    } 
    dialog -v mmp.dialog
  }
}
on *:DIALOG:playlist:sclick:*:{
  if ($did == 2) {
    set %add.files $$msfile( $+ %mmp.playdir $+ ,Select Media File(s) To Add,Add) 
    var %i = 1
    while (%i <= %add.files) {
      write addons\vidlist.txt $msfile(%i) 
      inc %i
    }
    loadbuf -ro playlist 1 addons\vidlist.txt
    did -z playlist 1 1 3
  }
  if ($did == 3) {
    set %vid.del $did(playlist,1).sel
    write -dl $+ %vid.del addons\vidlist.txt
    loadbuf -ro playlist 1 addons\vidlist.txt
  }
  if ($did == 4) {
    write -c addons\vidlist.txt
    loadbuf -ro playlist 1 addons\vidlist.txt
  }
}