Can't Build Lighting anymore in March Upgrade

[nickmarks]

I just upgraded...I have test box i subtracted out of world...put a light in it...build...and wait forever!

What is up? Any suggestions

[RJM74]

They do recommend that you use Additive instead of subtractive, give that a try instead and you may notice a big difference.

[nickmarks]

Yes! night and day.

There must be an error in this build with subtractive. If i do addative it builds like usual. But subtractive is EVIL long. To long for me to wait.