Sorry, but I was busy :S
So, WED shows 6 textures on the import process, and I use .png.
Easy to use the alpha and transparency with this format. The textures, all together, are 1 MB.
Here is the download link:
http://arnyek.blogom.info/content/level1.zip
Actually, this framerate is not a problem while playing. But it's just a beginning part of the map and is already big
So, I'm affraid of that the size will be huge in the future.
Can incorrect texture size cause such these things? I mean i.e. 512x256x32. 'Cause I use some with this size.