Added function to update of custom_gcode_per_print_z in Model from configuration

considering "colorprint_heights" option.

Changed thumb_up/down icons to better preview (feedback from #3256)

Commented some uncertain code

src/slic3r/GUI/PresetBundle.cpp

@@ -869,6 +869,9 @@ void PresetBundle::load_config_file_config(const std::string &name_or_path, bool
         }
         // 4) Load the project config values (the per extruder wipe matrix etc).
         this->project_config.apply_only(config, s_project_options);
+
+        update_custom_gcode_per_print_z_from_config(GUI::wxGetApp().plater()->model().custom_gcode_per_print_z, &this->project_config);
+
         break;
     }
     case ptSLA: