I'm getting a problem where L3DT hangs while trying to calculate the lighting map. It doesn't become unresponsive at all, it just sits there doing nothing on the "Calculating Lighting" stage and the time remaining stays at "Indeterminate". I have a quad core cpu and the load on all the cores while this is happening is pretty much zero, so I'm not entirely sure what its doing or what its waiting for. I left it for a few days over the weekend to see if it ever picked up and started going again, but it never did.
I checked the log file and there wasn't any errors in there, just the info messages about loading the different mosaic tiles. I'm at work atm so I don't have the project file handy so I can't remember exactly what the settings of the project I was working on are, but its split into 512x512 mosaic tiles, the bump mapping info was in the normals, and I was making a high res light map (8:1).