Problem
At this moment LambDynamicLights doesn't support dynamic light sources, which are blocks placed inside minecarts – lit furnaces, torches, fire, lava etc. In survival, you can only get minecart with a lit furnace, but using commands it is possible to set other blocks:
https://youtu.be/8LbCkMFOkSI

Solution
So, it would be logical and very cool to have minecarts with some blocks in them as a dynamic light source.