Unsuccessful with "OptiCore + LuxCore Lens" tutorial

[Garrett-Lundegard]

TripleLens005.zip
I'm trying to recreate simulation done in this tutorial: https://www.youtube.com/watch?v=3hln88ukiZI&t=615s

Here is the result I am getting:

It's a pretty picture, but not quite the symmetrical pattern achieved in the tutorial. Any ideas as to what I may have done wrong?
I remade each lens to ensure there was no error there, but no luck.

[Garrett-Lundegard]

By changing setting N1 and N2 = 64 during lens creation, I managed to get this picture:

Looks much better, but I wonder what is the difference that results in this image versus the patterns shown in the image from the tutorial.

[CodeFHD]

I have noticed this kind of behaviour also, but I am unsure of the reason behind it. If you increase N1 or N2 in small steps, there is a sudden jump at some point. I also did not do extensive tests if this depends on other parameters like lens curvature.