most buttons and such don't convert because of how they're specified.
I was able to convert any and every shape/object on the screen though that was any type of polygon by exporting, modifying the text file and reimporting into ME.
This was for a screen where it had hundreds of polygons drawn on it for esthetics (flowers, ground markings, etc. It would have been a huge pain to recreate it).
All the buttons were not save-able though. If someone was inclined enough they could write something to convert them roughly, but it doesn't happen often enough I guess.
The simplest way I found, wasn't to go in and modify the SE. but to create a new window in ME. then open both the SE and ME in a text editor, then copy and paste the code from one to another and it will take it just fine if the option is available for it. Otherwise it will throw an error up.