I have two users whom lose their localized Mechanical parts when they save down to Mech07. The parts don't convert to lines and arcs, they just dissappear and are permenantly lost from the drawing. Any help?
Not sure your mechanical parts was drawn in Model Space or Paper Space. But looks like it is in Paper Space using AMDWGVIEW command.
You can try AMVIEWOUT or EXPORTTOLAYOUT commands.
If your mechanical parts drawn in Model Space, you can try AECTOACAD command.
We also had this happen to one of our two 2007 users when said user would open 2011 drawings which had been saved as 2007 file type. In comparing the Options menus of the two 2007 installs, we found that the above user did not have "Show proxy graphics" selected under the "Proxy images for custom objects" drop down menu on the "Open and Save" tab of the Options dialog box. Once we changed that user's options menu to match the other 2007 user's options, that user was able to see the AutoCad Mechanical geometry.