Yes, first round results do count toward aggregated final results. Every round in every simulation builds off of the results from the previous rounds. However, if previous round results are unsatisfactory, one has the freedom to edit and change content to improve results for the next round.
Make sure each round is completed before running them. This includes any edits that have been made to improve previous rounds. After the"Run Simulation" button is clicked, results will be calculated and it will be impossible to go back to the previous round.