Hello,

It is currently not possible to import a LDD model in mecabricks. It would require a converter as part origins / references are different in both software.
However, I don't know if you already tried it but there is a software that can render LDD models. It is called LDD To POV-RAY.

it is possible now to import a model from LDD into mecabricks workshop. You go up to the top right corner where it says "File" click on that and a bunch of different things will display. Click on "Import" and a popup will appear. Where it says "Mecabricks click the down arrow on the right and it will show the words "Lego Digital designer" and "LDraw" click on Lego Digital designer and then click "File" it will take you to your saved LDD files and you can pick one.

Mind you this may only work on certain computers but the computer has to have LDD on it