Hi Tellie,
When you left us the qt6 version, I installed it, and put the qt6core.dll in the same folder of the nomacs.
I ran it and it worked perfectly, and I looked at a lot of photos and a lot of folders.
But, days later I wanted to open it again and it closed, seconds after opening. With an error in exceptq.
Editing the profile, I saw a mega line of a length of approximately 1600 columns, created with the qt6
They were the paths of each photo.
With the epm I left the line at about 600 characters.
I tried on the QT5 version, and it worked perfectly.
I put it back with the QT6 version, and it still works perfectly.
My conclusion : To have a correct profile in Qt6, you first have to have it created in Qt5.
Saludos