An odd sidenote, Visual FoxPro is fine
if I set the field datatype for the Integer to Character and converts on Select/Update.


Go into VFP help:
Remote View Data Types to Visual FoxPro Data Types

You can see this limit conversion for
SQL_SMALLINT / adSmallInt,
the conversion to a Logical

SQL num     VFP logical      SQL num
NULL     -> NULL          -> NULL
0        -> .F.           -> 0
#0       -> .T.           -> 1

is not supported.

The CheckBox support integer field,
but have a design bug

NULL  -> not supported
0     -> .F.           -> 0
1     -> .T.           -> 1
other -> NULL          -> 2

and not support the NULL value correctly.