How to make SFS packages for Fatdog64

Firstly, make a standard package as described in "How to make a package for Fatdog64".

Once you have done that and have a package file:

1. Extract the package into a temporary location, say /tmp/mypackage.
2. Run the following command:
   
   mksquashfs /tmp/mypackage /path/to/where/you/want/to/keep/the/result.sfs -noappend -comp xz -Xbcj x86
   
3. And then you can delete /tmp/mypackage.