I have an older vbxe.. still version 2.1 though. I have it in my 1088xld. I noticed on the u1mb information page that it showed the core being 1.26r. Which is a rambo core and since I have a different memory upgrade should be a version A. So I decided to flash the core. If I try to use FC.Com with a 2.1 core version it says i'm using the wrong core. If I pick a version 1 core it flashes, then has an error during verification. FC.COM says all 4 banks are empty.
Now if I use DCFG.COM, and pick a version 1 core it tells me that it's the wrong version. But a version 2 core seems to flash fine. So I flashed the vbxe with the new NTSC version 2 core. Color changes and everything looks awesome. U1mb info page now says version 1.26, no R. And some weird color glitches i've had for years went away(memory conflict perhaps?). Alls well right? Well today I fire up the 1088 and the color is back to Pal. Info page again says 1.26R. Like it's reverted back again. Not sure if i'm doing something wrong, or if this vbxe has issues. It has had a hard life, been in 3 different atari's.. several bodges on the outputs now, but does seem to work otherwise.
Something non related that I noticed on the u1mb info page as well. On the settings page stereo pokey shows enabled. But on the info page it says "not present". Stereo seems to work fine though.