Pardon me for bumping this old thread, but I was looking for something very similar, namely a popupedit with spinedit buttons and functionality.
I think what's really missing here is a special buttonstyle to display the up-down buttons above each other in place of one button.
Placing left-right buttons instead is a substitute, but it's a little counter-intuitive when everywhere else, the numericupdown / spinedit scheme is used.
Anybody found a way to pull this off?
Marco