I am using version 1.5.1. I had set it up years ago and went back and updated it with products. My problem is that the State and Zip code does not show up in checkout and it stalls at shipping address. In trying to fix this using suggestions I got in the internet I now have the "Administration/System" going to permission Denied in all but User/Used Groups. I am 86 and my Computer helper died a few years ago. I may have this old version but that does not mean I am knowledgeable so please help.
In the admin login can you get to System -> Users -> User Groups? If so click Edit on the Top Administrator (or any other group that looks for admins). Then select all in Access Permission and Modify Permission, then Save.