In this step, you don't have to activate the zap icon or go to the version control. (screenshots below)
All you have to do is go directly from the URL of https://epos.erply.com/typeyourversionhere
For example, you would like to go down to the 4.50.14 version.
You can go to your Chrome browser and type in to the address bar https:epos.erply.com/4.50.14
Then it should bring you to that version. (screenshot below)
Make sure that your Version Control is off as you do this, if it's not your POS will reload to the version control chosen.