anchor.diff:     ! Tight coupling routine for computing derivatives of continuous states
      ! this is modelled off what used to be subroutine DoRHSmaster
   
  -      REAL(ReKi),                         INTENT(IN )    :: t       ! Current simulation time in seconds
  +      REAL(DbKi),                         INTENT(IN )    :: t       ! Current simulation time in seconds
         TYPE(MD_InputType),                 INTENT(IN )    :: u       ! Inputs at t
         TYPE(MD_ParameterType),             INTENT(IN )    :: p       ! Parameters
         TYPE(MD_ContinuousStateType),       INTENT(IN )    :: x       ! Continuous states at t
  
positive.code: 
           ! step 1
  
           CALL MD_Input_ExtrapInterp(u, utimes, u_interp, tDbKi          , ErrStat, ErrMsg)   ! interpolate input mesh to correct time (t)
        
           CALL MD_CalcContStateDeriv( t, u_interp, p, x, xd, z, other, m, dxdt, ErrStat, ErrMsg )
           DO J = 1, Nx
  
negative.code:       TYPE(MD_ContinuousStateType)                   :: dxdt    ! time derivatives of continuous states (initialized in CalcContStateDeriv)
        INTEGER(IntKi)                                 :: I       ! counter
        INTEGER(IntKi)                                 :: J       ! counter
  
        INTEGER(IntKi)                                 :: ErrStat2   ! Error status of the operation
        CHARACTER(ErrMsgLen)                           :: ErrMsg2    ! Error message if ErrStat2 /= ErrID_None
  
  
        ! below updated to make sure outputs are current (based on provided x and u)  - similar to what's in UpdateStates
  
        ! go through fairleads and apply motions from driver
        DO I = 1, p%NFairs
  