I don't export to DWG very often, and certainly not with fills to hide what is behind.
The fill may mask elements from view, but the elements are still there and will be exported in the DWG.
Why the fill in the DWG does not still mask those elements I don't know - it could be an Autocad setting for masking/cover fills (I don't know).
To me if you don't want to see something, the best thing to do is hide it completely by putting it in a layer that you can turn off.
Barry.
One of the forum moderators.
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