The changes you made to SqlControls are ok.
One thing that we must beware of, is that when we insert for the first time a "Sql Table Control" (Sql > Insert Table) inside a form, the table must show at least one column, so that it will be externalized with t.columns > 0, and later on Internalize will work. But that is nearly obvious because when designing the form, we need to specify the format (width and align) of each column.
Thank you