...
If oCtl.TabIndex < lnIndex
   IF PemStatus(oCtl,"SEtfocus",5)
      lnIndex = oCtl.TabIndex
      This.FirstControl = oCtl.Name
   ENDIF
Endif
...

Don't forget to check if the found control has a SetFocus method. Also the code didn't deal with the only control in the fomr being a pageframe or grid, whereon you would need to drill into those objects to find the "first" control.