On Mac 10.7.5. Just updated to Scrivener 2.3 (and then to 2.3.1) and noticed a new bug when inserting text into tables. When the amount of text exceeds one line, it begins giving each letter its own line (screenshot is attached). If you hit return / enter you can enter text on the next line normally. Could not reproduce this error in text edit.
The tables are handled by the OS X text system, so it is something that should happen in TextEdit as well (since there is no code pertaining to tables in Scriv). If you copy and paste it into TextEdit, does it look the same?
To me, it looks as though you have just changed the second line indent so that lines after the text get indented. Show the ruler and check that - I just recreated this in TextEdit by messing with the second line indent.