Update Rollup 2 for SCVMM 2012 R2 - unable to start VMM service

I have a 2012R2 VMM installation where suddenly the VMM service refuses to start and I believe the problem is caused by Update Rollup 2. In the event log I see:

Application: vmmservice.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.Data.SqlTypes.SqlNullValueException
Stack:
   at Microsoft.VirtualManager.Utils.GlobalSetting.GetVMMServerAgentIdList(Microsoft.VirtualManager.DB.SqlContext)
   at Microsoft.VirtualManager.DB.ServerGlobalSettings.ReadServerData(System.Guid)
   at Microsoft.VirtualManager.DB.ServerGlobalSettings.get_Instance()
   at Microsoft.VirtualManager.Engine.VirtualManagerService.StartSQL()
   at Microsoft.VirtualManager.Engine.VirtualManagerService.ExecuteRealEngineStartup()
   at Microsoft.VirtualManager.Engine.VirtualManagerService.TryStart(System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.TimerQueueTimer.CallCallback()
   at System.Threading.TimerQueueTimer.Fire()
   at System.Threading.TimerQueue.FireNextTimers()

UR2 was first installed on the VMM host by windows update but I have since also downloaded the updates and applied them manually and also run the SQL on the database as specified in KB2932926 but the problem persists. Ideas?

All VMM components running on the same server with the DB on another server.

I have spent a bit of time searching for others with this problem and all I can find is this http://community.spiceworks.com/topic/471318-scvmm-system-centre-virtual-machine-manager-service-keeps-terminating - they gave upL.