The Standard Hours calc will use the Standard Cost EBQ number. It is important that this is set realistically, as the set time for each op is divided by this number, in order to get a sensible Std hours number. If left at 1, for instance, the full set up time will be applied to the Standard Hours for the part, generating a inflated number.
The Standard hours on the relevant item will not generate as Standard Hours, because it is a Per Unit measure and there are large denominators in the route operations - i.e. 1 hour to make thousands of parts.
For example: You would get a unit Std Hours calculation of 0.0011 - which is why the calculation does not error, but the display is rounding to zero.
Note: the standard hours number in the STKHEAD table is expressed in SECONDS. I am seeing 4 seconds, i.e. 0.00111 Hours