1. Levels

1st row: move up, move down
2nd row: edit level properties, delete level
2. Elements

Group: here select elements category.
1: move Selected Element up, move SE left, move SE down, move SE right
2: create element (in selected group!), edit SE (even those existing e.g. spaceship, yam yam, steel!), delete SE (even those existing!)
3: edit SE options configuration in a level, copy SE to..., move SE to...
3. Group elements

1: move Selected Elements Category up, move SEC down
2: Create Elements Category (look on the screenshot):

Next: Edit SEC Info (even those existing!), Delete SEC (even those existing!)
I hope this manager will be released before RND v.4.0.0
