Here is the setup -
I have selected a 8.5x11 paper size in Qimage. I then select a 4x6 photo size and place two photos on the page. It is set to Intelligent spacing on the options. Both photos appear in portrait format so there is room for another 4x6 photo below the two photos and the new photo will be in landscape format. All this works as you would expect.

However, there is enough room on the right side of the bottom photo to fit a larger than 4x6 so I created a 4x7 format. When I use this 4x7 to add a photo it always goes to another page (auto-crop is turned on), there is plenty of space for the 4x7. If I use the 4x6 the photo goes on the same page.
Now the question - if I choose optimum spacing, instead of intell-spacing option, the 4x7 doesn't go to the next page but is placed at the bottom.
Is there somewhere that these options are explained and exactly how there work. I thought Intell-spacing would be the smarter choice, but again it always goes to a second page when using this option.
I've looked but couldn't find any information on how these options worked or what the differences were on each. If you point me to the right area, I would appreciate it.
Thanks for any help.