If I were you, I would first resize the partition, and apply it. Then move the other partition.
If you try to do too many things at once, you get lost, and wipe your main OS because you thought it was another partition. Or maybe thats just me
I also think possibly because you haven't applied the first change, qtparted may be trying to apply the change to the original hard disk structure. Take it one step at a time and see how you go.