Checkbox can write to DB but not read from DB: Firebird CHAR(1) field.

I have a checkbox component connected to a CHAR(1) NOT NULL field, which can contain only a Y or and N. All records start with an N in the field. Sometimes the form will compile, the check box can be changed to Y for a record, and the Y will be written to the database for that record. After that, when I move to other records, the checkbox is stuck at Y for all records, even though the underlying record contains an N. So, it appears that the checkbox component in ScriptCase can write to the record, but it will not update itself when ScriptCase form app moves to a different record. Other times, the form will not compile, an error message is displayed, and I send it to ScriptCase by clicking the link in the error message.

It appears to be a problem with either UTF8 or CHAR(1) fields. I changed the DB to ASCII and used VARCHAR(1) and the checkbox SC8 field is working correctly now.