Samantha and Per,
Thanks for taking the time to add your investigations and results to this thread after I started it almost a year ago. Both your posts helped me to create a bake with the detail that had been missing in my first attempts a year ago.
A few notes:
For a reason I am unsure of, when making the transition to multires the resolution of my mesh increased substantially beyond what the instructor had although it was about the same at multires 5 (about 5 million faces). When I went to multires 6 it became 22 million faces, while the instructor’s mesh went to around 13 million faces. I think this may be part of the reason why a much higher resolution tile size was needed for the bake - I used 8192 x 8192 (it seems that Blender can’t go any higher? Trying to increase the tile resolution beyond this automatically reverts to 8192).
Using a multires ‘Level Viewport’ of 0, as Per noted, produced a flat looking bake with no detail, while a multires ‘Level Viewport’ of 1 worked much better, but a level of 2 produced the most detail. Going lower than 1 or higher than 2 produced flat looking bakes. I think the level one chooses for best results might depend on the max resolution of the multires mesh.
Again - thanks for adding to this thread. Hopefully it will help others in the future.