a) add dwg to the moviexts in the album configuration,
b) upload both t_plinth.png (notice that it has the thumbnail prefix defined in the configuration) and plinth.dwg (in that order, if your are using the upload page)
then t_plinth.png will link to the dwg file. When you click on the link, the user would most likely be prompted to open/save the dwg file, just like any other download link.
if you upload both a larger screenshot (plinth.png) and the dwg file , then t_plinth.png would be automatically created and album.pl would display the same thumbnail for both the screenshot and the drawing file. as both have the same root name.
J.J.
