First off, check your brake fluid to make sure it's filled properly. If it is, don't worry about it. If you get that same warning again after you've fixed the cluster, you might be looking at a loose brake fluid sensor connector or a knackered sensor.
Check the tail lights at the rear to make sure all are working properly. If they are, move onto the brake switch.
If your brake lights are working fine and you've wriggled the connectors in behind the trunk, you might be looking at an LKM fix (Light Control Module) although I'm not sure if the LKM is even remotely related to the cluster.
Check the fuses again and see which one(s) have blown, if any. If one did blow, then you are most likely dealing with a short circuit on one of the systems that fuse is fusing. If all looks ok, replace with another one just for good measure.
If all checks out well, I'd suggest you pull the cluster out and reseat any connectors on the cluster (take off and put back on). If that doesn't fix it, I'll put you in contact with someone who'll be able to help you more indepth...