I try to control the sequence of my elements within a code first itemtype. I have a code first item that inherits properties from a base item, the problem is then that the itemtype editor puts the properties of the base class at the bottom of the screen (and these are the most common properties). I expected to solve this by adding one property in the class that uses the same groupname as the properties from the base class that I wanted on top. The result is that indeed the correct group is displayed at the top. However altough I added [SortIndex(3)] to the new property it is still displayed above the properties from the base class that have Sort indexes of 1 and 2.
I would be very happy if this issue can be solved. However I would be much more happy if it becomes possible to add some kind of sequence to the groups, I realize this is difficult because the groups only exist in the items attributes, but maybe you can make it possible to add a priority parameter to the Group attribute and then within the editor generate the groups sorted by priotity. This will give us some kind of control over the item editor.