Reality Capture 1.4 \ I can't to save my project and after open it.

I uninstalled and reinstalled epic launcher and reality capture but the project didn’t open.

I am currently working on a new project. and To save time, a question arose.
I photographed the ground 4 * 4 meters, and I want to make a tile texture.

  1. Do you really need High Detail 780M and make high detail?
  2. Maybe the Normal Detail of 180M will be enough for on a lowpoly one?