Are you using a shader on the blocks? If that is the case, set the textures to flat, just to make sure that that is the problem. If it works afterwards, just send me the shader (in case that that is not a problem) and I will try to fix it for you which shouldn´t be too hard. In case you aren´t using a shader, try setting the textures to flat as well. If it works afterwards you know that the problem are wrong texcoords and that it is only a problem with shaded blocks. If it doesn´t work as well you can´t get more into the details for a bug report but you should do one anyways. (as long as it is not a shader problem)
I also have problems with the lightmapper. Lighting v2 looks a better then the other but there are still some heavy problems.
Other then that your project looks very nice and there is a great atmosphere on the screenshots
Edit: I did not notice that you wrote that they are moving very fast. That is really very strange.