Hello,
MobileSim provides an abstract interface to its simulated laser, and this is not represented in ROSARIA yet. So at this point only features represented in ROSARIA can be used in MobileSim (robot position, velocity control, bumpers, sonar).
Instead, you could simulate using Gazebo or Stage in ROS, and then later switch to real hardware using ROSARIA for mobile robot control and the hokuyo node for the laser.
Let me know if any documentation is confusing on this point, or if anyone has any ideas for how best to represent simulated devices in ROSARIA.
Reed