Also, don't name your buttons "bGame" . Lower case "b" followed by uppercase its the naming convention for a variable of boolean tyle in C++ (and unreal recognizes it) .
How does all this responsive stuff works for normal resolutions and ultra wide monitors? I have an UWGHD Monitor and i experience a lot games which have broken menus with my resolution. Most games don't even allow my native resolution. By the way, i would highly recommend to start with a z-order above 0 so you have still rom for lower numbers and increment the values by 10 or 100, so you can do changes later, without the need to change everything in the order, if you put in a lot of stuff later. It is similiar to the best practices for z-index in css. Regarding CSS, is there any way to use web based menues instead? I am a fullstack programer and do tons of frontend stuff in my dialy work. For me, it would be easier, to just use a web based frontend instead. But i didn't experience the ue ui in its full extend, maybe it also depends on how you gonna use it.
