flag glow light is affected by the map lighting so even with changes to radius and intensity, there are times where its overpowered by enough global light to be invisible
BE side hillking is good tester for this - the global light comes from behind spawn, so on the shady side of the valley, the flag glow is obvious - the other side thats in direct light, its totally invisible
i used to think this was a 1.40 lighting bug cause i didn't remember it in 1.30 but i checked and apparently it's always been that way