No the object has to be created in 18.
You could try embedding the object in a 20 file (in the embedded library).
Then save that back as a version 19 file, then open in 19 and save back as a version 18 file.
And hope you don't have any unique version 20 commands in the scripts that weren't around in 18.
This should convert the object back to 18 and I think it will keep the original GUID number that is how the object is recognised by Archicad.
Another option is to copy and paste the code from the 20 object into a new 18 object.
You will have to recreate each parameter one by one.
This will definitely change the GUID so it won't be recognised as exactly the same object in 20.
You will be able to use it in 20 but it won't replace the original 20 object automatically.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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