Yes, your first round results do count towards your aggregated final results. All of our simulations rounds build off of previous round results. Do your best during the first round because it does count. However, if you do not like the results from a previous round, you can edit your work in your current round to try and improve on them.
You will also want to make sure you have completed each round before you click "Run Simulation". This include any edits that you may want to make from previous rounds. After you have clicked the"Run Simulation" button your results will calculate and you will not be able to go back to the previous round.