Incomprehensible message Map Assistant

After copying a route into a new file, you are asked to replace the media file (which one?). After clicking on “Replace”, a finder window opens in which nothing can be selected.

Whoa, That is strange! How exactly did you get to this point? You copied a map layer from one slideshow document to another?

exactly, with copy & paste

I tried to reproduce this problem - but can’t!

Which version did you use? Can you provide exact steps to reproduce this issue?

Hi Peter, I can reproduce it in b18 too. In an existing file I marled 3 tracker an copied them in a new file 16:9. That all;

shall I send original FMS-file to you? 8.9 MB

Update: after duplicating the source file with (cmd D) and trying to reproduce the error with the duplicated file again, everything worked without errors.