I have both Lightroom 4 and Photoshop CS5. When I edit my pictures, I usually start with Lightroom, and then use Photoshop to add my watermark logo. I've noticed that the quality between the saved image from Lightroom and the result image with Photoshop is different. The result has lower quality. I've tried saving it as a PNG24 as well as the maximum quality JPG (Lightroom exports as JPG). Am I doing something wrong? Is there any way to add my saved logo using just Lightroom?

Can you post the exported logo using various settings, PNG24 should not degrade the quality of the logo asset.

A quick google will also reveal the process to adding a watermark in Lightroom. i.e http://www.lightroompresets.com/blogs/pretty-presets-blog/6162226-4-easy-steps-for-creating-a-watermark-in-lightroom

Not what I'm talking about. I have my own image as a watermark. I can get it to add it on Lightroom, but it doesnt really give me placement options or opacity options.