DWG Trueview 2013 shows block frames (DWG from AutoCAD 2006)

Hy All!

I use AutoCAD 2006 to create my drawings. I save it in DWG format 2000. My coworkers can open my drawings only in DWG Trueview 2013 or 2012. If they do so, they see all the frames from the blocks. In AutoCAD 2006 they don't show up.

This is the drawing in True view:

This is the same DWG in AutoCAD2006:

 My question is, how can i turn these frames off???

Greetings from Hungary,

Tothgra