my suggestion would be to look in the programming section for an existing insim, or getting off your duff and learning a language and coding your own. nobody will just up-and-give a demo user a fully working cruise insim. fat chance.
The INSIM_VERSION was updated to 8 when LFS updated to 0.6T.
The cruise server insim you have is likely still using INSIM_VERSION 5, so there have been a few changes that may have broken the insim you downloaded.
If you understand the code, you can find LFS Insim documentation (InSim.txt) in the LFS\Docs folder.