Update ...
Did so more research and there's definitely a pattern of only grey bars appearing for pics over a certain HxW ...
For example, it seemed to be working fine on recent uploads, then a member just added 3 pics that are 1279px ? 959px, they display fine, however, all three have a grey bar across the bottom.
I noticed that another member immediately afterwards uploaded some pic attachments that were less than 1024x768 and the watermarks show just fine on them ...
Hope that helps debug things ... :up:
Regards,
Doug
Edit: I've added another example that shows how large pics seem to a factor in triggering the grey bar. The pic attached is one a member just uploaded as an attachment and it's 2448px ? 2958px (scaled by vBulletin for internal storage to 532px ? 643px).