Hi William,
my feeling is that Wallacei is changing the input parameters and then evaluating the GH canvas for a single time (standard behaviour). After this single step evaluation, it initiates the evaluation for the next set of input parameters. Flexhopper on the other hand seems to update the GH canvas multiple times when a simulation is initiated for a certain input paramter set and the particle position are being updated.This could be the reason why Wallacei only updates the rectangular area and directly jumps to the next input parameter set.
You can see this behaviour if you initate a simulation and look at some GH components, which seem to update although they are not related to Flexhopper … for instance, the rectangular component is updating although input parameters are not being changed …

I tried implementing the counter in a different way using a C# compenent and a static variable. You can have a look at it - but unfortunately it did not solve the problem … 20201011_test 4.gh (73.2 KB)

private void RunScript(object trigger, bool reset, ref object counter)
{
if(reset)
c = 0;
else
c++;
counter = c;
}
public static int c;
}
Besides Wallacei I also tried using other optimization components like Galapagos. However, the problem is the same …
@William_Q: Did you have a look at some Wallcei examples that integrate Kangaroo? Maybe that gives some clues how we could do it with Flexhopper … For instance, Kangaroo offers the option to use the goat solver option, which only outputs the last iteration …
Another approach could be to use one main GH file where Wallacei is running with the optimization … and from their automatically open up secondary GH files where the Flexhopper simulation is running and evaluated … kind of a sandbox approach … maybe metahopper can be of help for this approach … https://www.food4rhino.com/app/metahopper
Regards,
Manuel