bablosoft has never mentioned the possibility of downloading any old versions of BAS. Change the versions in the link, older or newer versions may be available for download.
How to downgrade BAS? I updated BAS and I no longer can execute python code from the Batch tool. I think its something to do with admin access etc, but previously it worked. Also, cpu usage is way up. Are you guys mining with my CPU?
Previous versions of BAS are in the directory BrowserAutomationStudio\apps\