The IQ store's signature checker is broken

I used the "MonkeyC: New Project" option to create a new data field, then changed the compute function to

    function compute(info as Activity.Info) as Numeric or Duration or String or Null {
        // See Activity.Info in the documentation for available information.
        return -507453934;
    }

then exported it, and tried to upload it as a beta app. I got: