I am particle picking using RELION then using cisTEM for 2D class averaging. I import my files into cisTEM as a refine pkgs and everything works fine (initally). As I pick more particles in RELION, I import my updated file (with more particles) into cisTEM. However, I am running into an issues when class averaging. When I display my stack, I only see grey boxes (image attached below) and when I run class averaging all class averages are empty. Does anyone know what might be the cause and how I can fix it?