Archicad 18 can not use objects from Archicad 19.
When you save back your 19 file to version 18 I am not sure what happens with the library.
i.e. if you had the 19 library loaded and you save as 18 file then does it switch to the 18 library when you open it. maybe you will have to manually delete the 19 library and then load the 18 library.
Even if you do this I do not know if the 19 objects will automatically swap back to 18 objects - they might as they do swap if you go from 18 to 19.
I can't say for sure as I don't use the default libraries.
Maybe someone that does can comment further.
But definitely if you have to model in 19 you can still use (load) the 18 library and then you will not have any problems.
Or have your colleague upgrade to 19 as well.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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