Hello,

Which software do you intend to use to render the model?

Do you change the instances option to group by geometry and colour or group by geometry? This one is very important, it can divide the ouput file / computing time by a lot if the same parts are used often in the model.

Did you untick LEGO Logo option?

I intend to use Blender. I tried both by geometry and colour and just by geometry.

I didn't try unticking the LEGO logo option. I can't try right now since I reached my maximum allowance with failed attempts.

Would exporting into one of the other formats work better?

Also, it seems to me that an external converter to export would work better and would be more stable, rather than just package and download the file directly. Perhaps a downloadable program? Just a thought. 😃

If you want to use the template I made for Blender, export to Collada with the option Group By Geometry. I am not too sure why it crashes with just a modular building - 2 or 3000 pieces shall be exported easily even with the logo on studs. Which browser, OS, computer are you using?

The model is actually converted in local on your computer (no cloud stuff) so a stand alone software wouldn't be of much help 😃

I'm not entirely sure what the grouping is for, but that's what I usually do because you said so.

I'm using Google Chrome/Firefox and Windows 10. The problem is that a script on the Mecabricks page crashes before the dialog to save the file appears.

Do the Mecabricks models save in a file? And is it possible to download that file? Or is everything there cloud-based?

If the set is a published and public set, post the id of the model. It can be investigated further. Maybe it's just a model that's failing to export for everyone and it might require some fixing. If you're thinking that the script is crashing, it might be a good idea to post any errors if you see any.

Models from Mecabricks can be stored in a JSON file (if you know how models are loaded into a mecabricks scene), but they will be not usable to reach your target. The way this file is build up will not be compatible with blender. If you want to export this model, it will have to be by using one of the export options.