As per the heading, when an application's main form inherits from TTMSFNCRibbonForm, it loses the ability to "snap" to the sides of the screen. Similarly it doesn't respond to the Windows Logo key in combination with the arrow keys. Is there a workaround or a setting to reinstate this ability? I note that TTMSFNCRibbonForm inherits from TForm which has this ability, so I assume it is being overridden somewhere.
This is indeed a current known shortcoming (as this is based on a custom form implementation).
It is on the feature request list and we'll investigate whether we can add this behavior to the underlying custom form.