I've been meaning to mention this before ... and I bet I'm not the only one ... but it bothers me every time I edit or create a wall definition.
Since the wall is defined like this:
2018.05.16_16h00m58s_001_.png 13.04KB 2 downloads
Then logically ...
2018.05.16_16h01m56s_002_.png 54.39KB 1 downloads
It also makes much more sense when you are configuring pen colours and sizes.