Hey @mtecher ,
This issue is happening because the component is having trouble clearing out the files of a previous simulation folder so that it can overwrite it with a new simulation folder that contains the new GeoJSON.
I know that certain programs like Microsoft office will lock files when you open them. So if, for example, you had opened a scenario.csv file in Excel and didn’t close Excel while running this component, it could cause the error that you see there. You can always solve this issue by manually deleting the folder into which the GeoJSON is being written before running that component. But my guess is that just closing all of the applications that you have open with files in the folder should solve it.