Exporting collections of objects to a single DMX file is a perfectly ordinary thing to do and nobody has ever complained about it before. The format is specifically designed for it. Take a look at the sample DMX files from any of Valve's projects: a large majority have multiple meshes (e.g. 10) within each file.

I can nevertheless see how this is disruptive to specific workflows. I will not make your proposed behaviour the default for everyone, but I can add an option which enables it per-scene. You can then embed the choice into your personal default Blender scene. I'll need to spend some time ensuring that the current setting (which will become legacy) is configured correctly, so that backwards compatibility isn't broken.

Come back when you can write a civil post.

This means that the exporter couldn't undo the changes it made to the scene. The actual error isn't in the screenshot, but you can capture it by copying the full message from the console window.

I won't be able to reproduce this without the original blend file.

The link is broken. Please copy the text instead of taking a screenshot of it.

It looks like the file you are trying to import is invalid. Please upload it somewhere and I will inspect it.

Fixed in 3.4.2.

It's hard to understand what you are talking about, but I will guess. Transforms of unparented objects are not exported. If you actually want your model to have an offset, create an Empty at the origin and parent your model to it.

This is an internal Blender error. Please report it to the Blender development team and provide the .blend file you are exporting from.

Thank you for the report, your findings were very helpful indeed.

Originally posted by Zappy:

coupled with a bug where it un-ignores an object's parent's transforms(?).

Please describe this in more detail.