I was having the same type of error because I didn't do the upgrade procedure properly.
I ended up using the new 6.2 script, with a 6.1 database. The 6.2 script was calling for tables that were not in the 6.1 database. This caused Hal to error(blank response). I checked in the brain editor and realized(using the test debug function ) that my input that was causing the blank responses was looking for tables that weren't there, because I was using a 6.1 database, and the 6.2 script that I was using was calling for tables that are in a 6.2 database.
To solve this, I uninstalled my 6.2 Hal. Then I removed any brain files from the ultra Hal 6 folder. Next I installed 6.1.(which i didn't do at first...which caused the problem) Then I took a backup of my database ( with all of my learned knowledge) and copied it into the ultra Hal 6 folder -- renaming it -- halbrain.db(lowercase)(because it was originally called gretta3a.db....obviously you don't need to rename it if it is already halbrain.db). I then installed 6.2, and the installer properly took my database(halbrain.db that I just copied into the ultra Hal 6 folder earlier) and merged it with the 6.2 database, giving me a brain database called Hal6Upg.db .
this database contained all my learned knowledge plus the new 6.2 tables.
This stopped my crashing problem, and my blank responses.
hope this helps
-the dude