A historic-themed Rats project, originally for Source engine, new port coming to Unreal 4.
A copy of the map is exported to OBJ with full UV/texture mapping via the awesome tool Crafty.
From there, I have to setup lighting so that both Source and Max are as equal as possible.
For Max, it only takes 1 light with Mental Ray (expensive FG and GI)
But to replicate the same in Source requires about 50 spot lights to simulate the same 'bounce' or global illumination.