I worked on a test map for the upcoming unsung for arma3 project. I added several libs of custom pbos. When placing building objects they cannot be seen in buldozer preview, but in the arma3 game. I cannot manipulate the buildings in terrain builder either.

It looks like they have been assigned to a different layer or so. From the lib I can still select them and opt to delete them from the lib.

If needed I can make the project available for download, it's around 160 MB as 7zip.