Tutorials: Preparing a MPD file for Official Model Repository compliance

Preparing a model to follow the Official Model Repository specifications can be a daunting task, as there are many little details to take care of. Fortunately, the MPDCenter tool comes to the rescue!

Setting up MPDCenter to find your LDraw folders.

These settings are located in menu Options -> Options

  • If your LDraw folder is a clean one, without any unofficial part, set the path to the pure official folder on it as well as your LDraw base folder. Set the unofficial parts folder to the folder that contains your unofficial parts (doh')
  • If you mix your unofficial parts with official files, download an up-to-date complete.zip and unzip it in a folder, then set the path to the pure official folder on it. Set your LDraw base folder and unofficial parts folder to your regular LDraw folder.

    MPDCenter - Options

Preparing your MPD model

This tutorial uses a model of the UCS Millennium Falcon by Roland D. both in its:


  1. Name your .mpd file as "xxxxx - name of set.mpd", here "10179 - Ultimate Collector's Millennium Falcon.mpd"
  2. Launch MPDCenter, open your .mpd file. MPDCenter trundles a bit - your file is NOT OMR conform!

    MPDCenter - File is NOT OMR conform

    MPDCenter performs some checks - responding with the following error messages:

    • Name of the container .mpd file - Is MPD filename OMR conform.
    • Names of the subfiles - All filenames in the MPD are OMR conform.
    • Structure of the .mpd file. The FILE xxx entry has to corrispond to the Name: xxx entry - All Name entries are like filename.
    • Mirrored parts in the file - Mirrored parts free
    • ~Moved to parts in the file - ~Moved to parts free.
    • Unofficial parts in the file - Unresolved references free.
    • All licences set to"redistributable" - All files have correct License.
  3. In the tree window (left pane), select the main model of your file (here main.ldr) then select from the contextual menu Edit -> Header dialog.
  4. In the dialog that opens, set author name, theme, etc... and most importantly the license as redistribuable (a not-redistribuable file can't be OMR compliant), click Apply.
  5. Answer Yes to apply the header data to all files in the .mpd, and Yes again to allow MPDCenter to rename all files in the .mpd to be OMR conform.
  6. MPDCenter does its thing, then (because this file contains specialized parts - the bended 47996 has no redistribuable license) complains that the .mpd is still not OMR conform.
  7. To solve this issue, click on each specific part file in tree window, then right click on it, and set license entry to redistribuable. Note that this step is not needed for models that don't contain specialized parts (or if the parts already carry a redistribuable license).
  8. Check again for OMR conformity via the menu Information->LDraw OMR check. This time, we get references to ~Moved to parts that should be updated (in the MPDCenter options it is possible to make this update automatic on file load).
  9. To do this: Edit -> Update '~Moved to' refecences
  10. We are almost done... the last step is to include all unofficial parts to the .mpd so that it remains consistent even if unofficial parts are renamed, moved or rotated. This is actually the most important step of all... To do this: Import -> Import unofficial files.
  11. Save the .mpd file.

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