Missing image files

Hello to everyone,
I have received a very large 3dm file which, when opened, shows that 63 image files are missing. What can I do to either replace all of these missing files or do without them? Unfortunately, so far I can do nothing more than press continue. But the next time I open the file, the same message appears again?
Also, after opening the file for the first time, a folder called “_embedded files” was created. There are about 35 material pngs in here.

Because the model is also extremely large and cumbersome - is it possible that this has something to do with it?

P.S. Unfortunately, I can no longer ask the sender for the missing image files (competition, deadline over).

Hi ToGo -

Select them in the list and use the Remove button. Then save.
-wim

thanks, but that was the first thing i tried. Nothing happens: the files cannot be deleted from the list.

It seems to me to be a bug if the option “remove” is offered, but nothing can be deleted.
And here: Missing image files it is described that “purge (textures)” would delete the links to the missing files.
Unfortunately, this does not work either (Rhino 8, latest stable version / Mac). As a last chance I have now replaced object by object … but maybe someone could take a look at this?