Get Galapagos to wait for external simulation

I am trying to connect Grasshopper with an external building energy simulation tool by a .bat-file and some text-files. The simulation time varies between a second and a day. The problem is that I want to use Galapagos or Goat to optimize some parameters and I do not know how to get these to wait until the result is ready. Right now they vary the parameters even if the result has not changed. After the simulation there is also some result post processing inside grasshopper that can take a few minutes. Any ideas how to get the parameter optimization to work would be helpful.

Sincerely
Max