Is there a limit to the number of items in a folder in Photo Gallery?

I have a number of folders that contain 200+ photos. They show fine in the library but when I attempt to use Photo Gallery to manage them it appears to only recognize 175 items. I have serveral instances of this and no folder shows more than 175 photos. It does not appear related to space/size but rather quantity.

Photos are normally stored on a network drive connected to the usb port on my router. The drive access works fine when connected to a USB port or hub directly to the machine. The problem manifests only when connected via the WD router and only with Photo Gallery. (This has been cross posted on the MS support community site)

Has anyone had a similar experience or even better, found a solution?

Thanks!

Windows Photo Gallery 2012

Build 16.4.3505.912

Win7/64

Router WD My Net N750

WD Passport Drive - 500Gb

There seem to be an issue with the way that Photo Gallery organizes the pictures. Maybe some of the other users can give you an idea on how to solve the problem.