Installing a UXP panel
This page offers instructions on how to install a UXP panel locally from a downloaded CCX file (this apples to the new UXP version of Lumenzia). If you do not have Photoshop v22.5 or later, you will need to run the CEP version of Lumenzia (see here to install the older CEP version of Lumenzia). If you are trying to install Web Sharp Pro - that is also a UXP panel, but is distributed through the Adobe marketplace rather than as a standalone CCX file (see here to install through the Adobe Marketplace).
Installing from a CCX file:
That's one of the main benefits of UXP, these panels are quite easy to install generally.
Note that if you have the CEP version of Lumenzia installed, it may be ideal (but is certainly not required) that you uninstall it or close it so that you free maximum resources for Photoshop. Simply closing it and restarting Photoshop gives you all the benefit, uninstalling it will save a tiny bit of extra space on your drive.
If you run into problems, please see the troubleshooting section below.
CCD says you do not have a compatible app installed:
The CCX file won't open or you get a warning "Creative Cloud cannot open files of this type.":
I installed the panel, but cannot see it in Photoshop: