L-Corona (12 tasks)

Puzzle description:
The puzzle consists of 15 L-pentominoes (one in a different color, here in orange) together with a tray. But the main tasks takes place outside the tray: Take the orange piece and n of the blue pieces (n=4, 5, 6, ..., 14 for 11 different tasks) to build a corona around the orange L. A corona is a ring using the same kind of pieces without overlappings such that the whole boundary of the central piece is touched by the corona and every corona piece touches the central piece in at least one point. Note that the corners of the central piece must be fully surrounded. Two pictures with coronas using 6 and 11 pieces are included.
The 12th task is to pack the 15 L's back into the tray.

References:
G4G12-Video by Craig Caplan: https://www.youtube.com/watch?v=OX2Y6CSonz0
If you can read German: Mehr Informationen gibt es in https://welt-der-geduldspiele.blogspot.com/search?q=3D-Druck

Puzzle difficulty:
The number of solutions varies for the different tasks betwee