If you got a persona error in v0.622, it will probably result in a state where your core story cannot advance. Fortunately, it's not too hard to fix the problem. Open your RPG save file in a text editor and search for "*CS_C_Greeting". You'll find a line much like the following:
*.23_GoGreet <*CS_C_Greeting .23_GoFoo>
This is the line you need to edit. You have to do two things: 1) remove the star from the beginning of the line, and 2) replace the *CS_C_Greeting bit with the command "GOTO". Doing this to the above example should result in the following:
.23_GoGreet <Goto .23_GoFoo>
When you speak to the NPC now, the greeting will be skipped over but the rest of the conversation should work just fine.
