Okay, Spirit, finally I re-installed priv-remake and wcu, so now I see the new bubbles.
They are gorgeous!
There's a technical problem with brightness, though; and it's not a matter of making them darker or brighter. The problem is that they are alpha blended, which is not the effect you want. (This was probably the problem with the original bubbles, as well.) When something is alpha-blended, it means that whatever it is shown on top of, --i.e. the "background" color, is multiplied by a constant, say 0.6, and what you're alpha blending on top, its color is multiplied by the 1.0 complement, --i.e.: 0.4, and the results of the two multiplications are added. In the case of a black background this seems okay; but in the case of a bright background it becomes weird, because if the color of what you're drawing on top is actually darker than the background color, it will darken it; and if it is about the same brightness, it won't show at all. So, it's as if the rings were painted with acquarel on a transparency, which can appear brighter or darker than the background. Not what you want: You want them to look "electric"; you want them to brighten any background.
The solution, if you really want to preserve some transparency, but you want them to look like light "sources", would be to tell OpenGL to ***ADD*** the color to the background, with saturation. That way, any background other than pure white will be brightened by the rings. "With saturation" means that if the background is white it will stay so, rather than numerically overflow onto some dark color.
Another solution would be to use color overwrite, without transparency, like the reticle lines in the HUD, though it wouldn't look as gorgeous.
You need to ask Hellcat or some other VS engine developer how to change the color mode from alpha to additive blending. I'm not familiar enough with the engine yet to tell you.