You also stated "Version CR 8.5 and below will, CR 9 and above will not." That led me to believe that CR 9 will not treat a Varchar(256) column as a memo.
What I am parsing is a string of email address information that includes an identifier for the person's location ("ou="

. Below is the SQL I have used to parse this information and the CR SQL Expression I have tried to create. The problem with CR SQL Expression is that the Clients."Email Address" is not listed in the "Field Tree". I am assuming that this is because CR is treating this column as a Memo field. This could very well be an incorrect assumption on my part. However, the problem still remains. I get "Error compiling SQL expression: ." when I try to "check" or save the SQL Expression below.
----- CR SQL EXPRESSION -----
{fn substring(Clients."Email Address",
{fn LOCATE('ou=',Clients."Email Address"

} + 3,
{fn LOCATE( '/', Clients."Email Address", {fn LOCATE('ou=',Clients."Email Address"

} )} -
( {fn LOCATE('ou=',Clients."Email Address"

} + 3 ) )}
----- SQL STATEMENT -----
----- This works in SQL Designer
select substring("Email Address",
charindex('ou=',"Email Address"

+ 3,
charindex( '/', "Email Address", charindex('ou=',"Email Address"

) -
( charindex('ou=',"Email Address"

+ 3 ) ) as ClientLocation
from _smdba_.clients
where "Email Address" is not null
----- SAMPLE DATA -----
MAPI:{Shaner,Sharon,FORT WORTH,Customer Service}EX:/o=AlconLabs/ou=USFTW/cn=Recipients/cn=07312shanersr