This is a remix of Customizable Modular Square / Hex Shelf (incl. Benchy Shelf) by JohnOldman.

I like the original design, but if you have a lot of Benchies, you have to print a LOT of joints and shelves, so I decided to butcher his SCAD file to come up with a single shelf that can hold 5 Benchies. I'm still learning SCAD, so be kind with your comments.

Changes from the original:
1. Added a new component called a "multishelf" - a version of the shelf that holds 5 Benchies.
NOTE: This component uses a fixed width of 200. It ignores the width parameter, but does use the depth and benchy footprint parameters. If you set the depth too small, the benchy footprint will run off the front and rear edges.
2. Added a rotation angle parameter to the SCAD file to adjust the orientation of the Benchy footprint because I wanted them to point straight out, but still wanted the option to change that. A rotation angle of 90 points straight forward. It's adjustable in 45 degree increments.
3. Added an offset amount parameter that moves the Benchy footprint left or right from center. 0 is centered, negative numbers move the Benchy footprint to the right and positive numbers move it left. This allows you to adjust the Benchy footprint so that it doesn't interfere with the joint when creating a multishelf. (It's a klugey fix, but it works.) Some rotation angles seem to need this adjustment and some don't.

I've included copies of some of the original STL files from JohnOldman and a "multishelf" STL with the Benchies pointing straight forward.

EDIT 8/9/2021: Adding three files provided by Balu: two custom walls and a new clip for labeling shelves . I also modified the SCAD file to clarify that the width parameter also changes the height of the wall - so that parameter is used to make the shelf wider or to make the wall taller.