leaking show tray?

have you tried the outlet or waste fitting it may be the problem if the leak is showing on cieling below the shower you need to check under the tray also is there an enclosure fitted if so has the sealant been applied to the external horizontal sections only .If the internal bottom sections of the enclosure frame are sealed any water that gets into the area under the frame cant get back into the tray.sealant should only be applied to the external side of frame But all vertical sections inside and out must be sealed also if you have shower valve set in wall check sleeve around valve body it may need sealant around it

steve the plumber
October 2008