M3-Mudlake [in ver 2.2]

i have a new track now, Mudlake
i don't know, why the track is so big (file-size), how can i make the track smaller without loss of quality?
it is an smaller track (lengh), but not so small, it also has some small bumps (for example on the crossing in the image), but that is ok, if itis not hard to drive.
i don't know, why the track is so big (file-size), how can i make the track smaller without loss of quality?
it is an smaller track (lengh), but not so small, it also has some small bumps (for example on the crossing in the image), but that is ok, if itis not hard to drive.