Well, first - it does NOT error when E-mail is filled and checkbox is not checked.
However - I understood the checkbox validation to mean that the CHECKBOX would get an error IF the E-mail was NOT filled.
The 3rd option for checkbox in the extension is: "This must be filled" and then I select my E-mail field.
I understand this to mean that if the E-mail is NOT filled, THEN I would get an error beside the checkbox -- not the other way around.
Checkbox validates fine if it is set to "ANYTHING"... but I want it to validate ONLY if the E-mail field is NOT filled.
I sent you the file by mail, if you could, please, take a look at it.