Just did a quick test and no problem with basic and composite walls merging.
David, is the hatch pen colour difference in 24 deliberate by you?
Or is that suggesting there is something different about the walls - graphic override or renovation filter?
Maybe you could select the walls in 24 and save as a module.
Then zip and attach the model here for us to have a look at.
One of the forum moderators.
Versions 6.5 to 25
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