OK. Just installed version 5.7.4.2. but now get the errors (below) when simply adding page :(

I tried going back to my older version (5.7.3.1) that I had installed, but now this has started throwing errors.

Not only that but the theme that I bought (Fundamental) and which worked in 5.7.3.1 doesn't work in 5.7.4.2

I'm going to try 5.6.3 'cause 5.7.4.2 is definitely still a Beta version.

Could someone point me in the right direction for manually installing 5.6 on plesk?

Thanks

{"error":{"message":"An exception occurred while executing 'select cID, msLanguage, msCountry, msNumPlurals, msPluralRule, msPluralCases from MultilingualSections where cID = ?' with params [\"1\"]:\n\nSQLSTATE[42S02]: Base table or view not found: 1146 Table 'Concrete5_6.MultilingualSections' doesn't exist"},"errors":["An exception occurred while executing 'select cID, msLanguage, msCountry, msNumPlurals, msPluralRule, msPluralCases from MultilingualSections where cID = ?' with params [\"1\"]:\n\nSQLSTATE[42S02]: Base table or view not found: 1146 Table 'Concrete5_6.MultilingualSections' doesn't exist"]}