Well,
Just upgraded to 2013. And just like 2012, it has some clean-up issues (see http://forums.augi.com/showthread.ph...61#post1138761). In this case, there are a number of things that are apparently hard coded into the program that won't let you delete.
I like to keep clean drawings, with only the things I'm using in the drawing file. However, I've found these items that C3D insists on keeping.
Blocks:
*Paper_Space0
*U1
*U2
Detail View Style
Imperial24
Linetypes
Phantom2
Section View Style
Imperial 24
The Detail View Style (reached via VIEWDETAILSTYLE) is a fixed name, and you can't even rename it (to, like, Standard)
The Section View Style (reached via VIEWSECTIONSTYLE) is also a fixed name. But, the line type "Phantom2" is in here, so you can change it, and ultimately purge at least that line type.
I don't know where the blocks are used.
If anyone has suggestions on how to clean these or get rid of them, I'd be happy to entertain them.