UPDATE: I updated the model to allow for vertical tiling. Also I put four hook adapters on the back, but only use hooks on the top and the bottom ones are just for support. If you already printed some out, they are good for using as a top row. The new models have a :) on the back to help discern them.
I just jumped into Skadis to elevate my paints from the desktop to the wall. None of what I found seemed to have enough density, so I adapted a previous model I made (300mm wide Vallejo Paint Rack HobbyZone replacement by Jumpster | Download free STL model | Printables.com) to fit a 160x160mm profile. I ended up having to completely redesign from scratch, but in the end it works and rather than the 10-15 bottles I've seen in other designs, I can fit 27! (actually 30, but it requires 6 half bottles). Since it's based on 40mm widths, you can tile the holder horizontally or vertically as much as you need - because of how the hooks work, you'll want to start from the bottom.
In order to make it possible to print without supports, I use the Skadis Hook Adapter which needs to be glued to the back of the plate. To support “bottoms-up” storage, I added holes to the plate, so the adapters are customized to fit around the holes. They have a foot at the bottom which helps with alignment when you glue.
The included 3MF file has the paint holder along with the adapters, and hooks you need to complete the assembly
The author remixed this model.
The adaptor blank is modified to conform to the topology of this model