I see that there are a bunch of people having issues with slow compilation times in 3DS Max. I mentioned this in the facebook group and Jules believes "it’s definitely an object gathering overhead issue" within the 3DS Max plugin.
I noticed the slow compilation times when I was working on my arch viz projects. I decided to do a simple test using 10,000 arrayed cubes with a simple grey diffuse material.
Here are the compilation times
10,000 individual objects
3.08 - 8 minutes 2 seconds
V4 - 6 minutes 23 seconds
Same polycount - cubes joined into a single mesh.
3.08 - 1.23 seconds
V4 - 1.13 seconds
Attached is a screen grab of the scene