1024x1024 should be enough for inner screen, I'm not pro, but you can make alpha channel out of anything, you just need good base picture and then play with modifiers till it is B/W in correct way.
I took this
made this just now, it should be good as an alpha channel placeholder for some time
As for rimblur getting transparent in some angles - it might be the issue with priority in KSeditor, I have had a lot of head aches with XJ13 rimblurs, a lot.... final one was that it needed toned down map, because it was crazy shiny and reflective, took a while to figure it out.
I took this
made this just now, it should be good as an alpha channel placeholder for some time
As for rimblur getting transparent in some angles - it might be the issue with priority in KSeditor, I have had a lot of head aches with XJ13 rimblurs, a lot.... final one was that it needed toned down map, because it was crazy shiny and reflective, took a while to figure it out.