I know this has probably been covered a thousand times but...
I can apply a watermark in the Slideshow Module and get it exactly how I'd like it (positioning/opacity/etc..). However, it can then only be exported one at a time and with a black border around each image, which I do not want.
I have tried the LR2/Mogrify plugin, but not having any luck with that either (probably due to my own stupidity).
