Quite unlikely you'll find this. However, most switching power supplies follow common designs, and if you look up the ICs reference you might find reference designs in the datasheet or application notes that are close to it.
As for zener diodes, you can usually test them in-circuit with the multimeter in continuity mode : as regular diodes they'll pass one way, and not the other way, since the zener threshold isn't met for it to pass in the other way. Testing the actual zener voltage wouldn't add more I think, usually they just fail completely, either break or pass always.
Sure the capacitors are ok in there?
What's the symptoms?