(2020-04-21, 2:34)N. W. Perry Wrote: So it must be something with LDD; and since the grid looks fine, I'm guessing it is just that the parts are missing from LDD.
I can think of two issues not mentioned yet.
Do you have a fresh copy of the file "ldraw.xml" in your LDD program folder?
https://www.eurobricks.com/forum/index.p...sion-file/
If there's no translation formula in that file, ldd will remove your part.
Have you used an "illegal" mounting method in your assembly?
Some assemblies we do IRL, and in LDCad, is not accepted in LDD, and the part is removed.