parametric cells do not export to dwg!!!

As the title says. Parametric cells do not export to dwg. 

WTF bentley - it would have been helpful to include this in the help. 

After spending an age learning these tools, then developing cell libraries and then placing the content, creating drawings etc. I now find out that parametric cells DO NOT export to dwg. No placeholders, no warning, just omitted content.

Is there a method to enable exporting of these elements? If so where? 

very useful feature parametric cells, however, if they don't export, what is the point, this makes them unusable?????????????????????????