I am able to fit plasma concentration time data with the WinNonin model 4:: it is one cpt model with first order absorption and elimination , lagtime and v_F. The fit is fine, but it is after fitting I want to simulate multiple doses say 2 doses that I am having sporadic difficulty. I do not know how to do a simulation with this program. I know how to do it in WinNonlin and did it for 15 years. I ned the steps on how myou simulate after fitting and what not to do. TO SIMULATE;; (1) you no longer need the concentration column mapped …all you need is times that you use for the simulation to be mapped…yes? (2) you still need the box checked that you had checked for the fitting and additionally now you check the simulate box (3) Below the diagram of the model and the simulation checkbox you are asked or units for units to enter. I enter ng/mL. (4) I enter the doses to 2 for number of doses and then type in time and dose in the Table. Doses are in mg but the plasma concentrations are in ng/mL. (5) Next I make sure that the estimates I obtained from the fitting are in place for the simulation. (6) Check the dose box again and run the program RESULT: The shape of the simulation is fine, but the scale of Y axes is vast. Please can send to me the stepwise instructions on how to simulate after fitting. I am stuck. Angus 
Angus - re-fit your original model with dose in ng, then simulate with dose in ng the wnl classic model handle dose conversions well when fitting, less well in simulation so remove this problem from the equation and I ma sure you will be good. Simon Also a couple of years ago I recorded an instructional YouTube video for converting a fitted Classic model to simulation mode; http://www.youtube.com/watch?v=rH6hCcOeWmw ; it’s only 3 mins long as it starts halfway through because I did fitting as a separate video. Let me know if it helps as we intend to record more.
Thanks Simon: For some reason I have been assuming that the program interconverts units and one could use the dose in mg and the plasma concentrations in ng/mL. I now see that this is not the case for simuolations. Angius
Simon: this approach is excellent. I see that instead of copying and pasting the fitted paramaters over for simulations you map them over after fittin to the estimates for simulation. I must try this. I think this is the way to go for teaching. There are so many details that are important. Thanks, Angus