Finished the MRTM model.  Fit seems to be better than MRTM0 as in models justification.

Finalizing the #2 MRTM model...

Added a "graphical verification plot" feature to MRTM0 modelling.  Equation is rearranged to the form C(t)=....  So the tissue TAC can be plotted over the model TAC.  In this example dont be discouraged by the mismatch as I drawn an arbitrary "Reference receptor-free Region".