I attached the panels with Tesa power strips. The supplied strips are not usable, they leave ugly residues on the panels and on the wall!

From my point of view, little by little is the better way. Depending on the wall condition, dirt is produced during drilling, which then sticks to the panels that are already glued on. In addition, a mistake during drilling can cause damage to the panels.
Gradually, on the other hand, more planning and precision is needed when measuring the drill holes.
I personally used this method and am satisfied with the result.
A tip for mounting on concrete/brick walls:
The screws supplied are much too large. For the weight of the Aurora, much thinner ones are also sufficient.

I glued everything, but with stronger double-sided adhesive pads. It even works on the ceiling.
If I were to use the brackets, however, I would only glue the individual panels together (to avoid gaps between the panels).