Jersey Dude may be trying to review images without having Lightroom generate Previews first. In the Library menu find Previews and generate Standard Previews or 1:1 Previews, depending upon how you want to review images.
But, specifically on the topic of sharpening: sharpening is best handled as a three-step workflow: input or capture sharpening, creative sharpening, and output sharpening, and this order is important.
Capture sharpening is intended to restore sharpness that may have been lost at capture time. In other words, this sharpening should bring back any sharpness a Bayer filter may have taken away, for example.
Creative sharpening is the thing most people do: adding sharpening during image editing. Strictly in this ideal process, however, creative sharpening is used to add sharpening only in focus or active areas, for example.
Output sharpening is used to sharpen the image for a specific type of output at a specific size. Output sharpening will be different for screen or print, and will also be different if printing a small print on paper or a large print on canvas, for example.
Lightroom provides two opportunities for sharpening, effectively creative and output sharpening.
- Creative sharpening is in the Develop Module, in the Detail area.
- Output sharpening is in the Export window, in the Output Sharpening area. (Output Sharpening was added to Lightroom 4, FYI.)
I'm not very familiar with BreezeBrowser, but it sounds like that might be doing some capture sharpening for you automatically? I don't know.