Jubilee must be powered up with tools off the carriage. In practice, this is will happen under normal operation, as slicer packages can be configured to end their program by parking the current tool. However, it is possible that the printer loses power with a tool installed in the carriage. In this case, the machine cannot recover on its own, and you, the operator, must remove the tool from the carriage and park it while the machine is turned off.
An empty bed plate must be installed on the machine in approximately the correct angle. If you are 3D printing with a removable surface, this surface must also be installed. When the machine homes, it will run a 3-point bed leveling process to fix small angular misalignment. However, if the bed is misaligned more than about 5 degrees, the bed cannot align itself. In this case, power off the bed and rotate the couplers manually until the bed is approximately level.