How do I reorder my stack Fiji?
You can also rearrange the order of slices in a stack using the Stack Sorter tool. Go to Image -> Stacks -> Tools -> Stack Sorter. You can then move a slice forwards or backwards using the arrows (1) in the options box.
What is stack alignment?
"Stack alignment" just means the address of the stack (SP or ESP) is a multiple of the machine word size (so always divisible by 8 for 64-bit mode, 4 for 32-bit, 2 for 16-bit).