I get this Error message when I wanna build the light:
**<None> === Lightmass crashed: ===Unhandled Exception: EXCEPTION_INT_DIVIDE_BY_ZERO
Unhandled Exception: EXCEPTION_INT_DIVIDE_BY_ZERO
0x000000013fc08aed UnrealLightmass.exe!UnknownFunction ]
0x000000013fc10dd4 UnrealLightmass.exe!UnknownFunction ]
0x000007feb2aa9128 UnrealLightmass-Core.dll!UnknownFunction ]
0x000007feb2aa3b07 UnrealLightmass-Core.dll!UnknownFunction ]
0x00000000770159cd .dll!UnknownFunction ]
0x000000007727383d ntdll.dll!UnknownFunction ]**