I think this has been discussed earlier, but I couldn't find any solution yet:
How can I modify the order in which the menu items appear in the "X" menu (mb-applet-menu-launcher)?
I have just modified a bunch of .desktop files here, and the mb-applet-menu-launcher rearranged the items afterwards. However, it did that in an almost-alphabetical manner, but some items fall out of this scheme.
What criterion does the launcher use to sort the items?