I have Web Portal Web Portal r9.7.0-910-20171213 installed. However, I want to go back to the slightly older Web Portal r9.7.0-910-20171012 (215MB). Can I do that?
Answer: No. The database initialization will not allow that.
To make that so, you would need to first restore your underlying database to the earlier version also to then be able to reinstall and use the older version of the Web Portal software with it.