@Frank
Could it be,that the used shader is the reason for your fps? I have the same problem with it,but I have not tested it with the terminal26 programm.When I only put a terrain into my level and use the multitexturShader,I also have only 25 fps.The same terrain without shader = 100!!!!!

I checked only the demo and did not change anything. I think it is because of the shader, because of scripts and textures. A mixture of everything.