If you have printed with Mixbook

[Stacey42]

what size pages did you upload?

I am having no luck finding any specs for anything but background & they want 4429x4499 for a 8.5x8.5 book (which seems odd as 12x12 is only 3600x3600) and then they mirror the image I put on the left hand page if I use it as a background! I found a full bleed page layout to use but I cannot find what size to make my layout to allow for cropping.