Want to jump right in and publish a slideshow? You're in the right place.
If you haven't already, follow the Installation instructions to get SlideShowPro for Lightroom installed.
Launch Lightroom, and in the Library area either manually select a group of images, or select one of your predefined Collections or Folders of content. The Filmstrip at the bottom of Lightroom should update with your chosen content.
Click on the "Web" link at the top-right of Lightroom's navigation, and then select SlideShowPro for Lightroom from the "Galleries" drop down. The Web interface should update with a live preview of SlideShowPro in the center work area.
Open the "Templates" panel in the far left column if not already open, and choose one of the default templates SlideShowPro for Lightroom comes with (if you don't see any, refer to the Installation instructions).
Click the "Preview in Browser" button at the bottom of the center work area, or click "Export" at the bottom of the right column to publish out your content. You should now have a functioning slideshow!
We recommend using an FTP program to upload your slideshow your web host. We'll leave this step up to you as there are many options. Here's one suggestion: Create a directory on your web server that will hold all of your slideshows. Then, upload each slideshow into a subfolder. E.g.: /public_html/galleries/2009_10_joneshollywedding, /public_html/galleries/2009_11_smithjohnsonfamily, etc.
You want to make sure that you've uploaded everything correctly. To do that, you want to view the slideshow on your web host in your browser. Let's say my domain is www.domain.com and I've uploaded my slideshow to /public_html/galleries/2009_10_joneshollywedding'. I'd navigate to http://www.domain.com/galleries/2009_10_joneshollywedding/index.html to view the slideshow I just uploaded. If that worked, great! You'll have to figure out where you went wrong if it didn't work.
This step is completely optional. You can simply direct people to the index.html file in the subdirectory you just uploaded. However, this will not have any navigation back to your site. You may want to make the slideshow look like it's part of your site (navigation, format, graphics, etc). To that end, you'll need to use your favorite HTML editor (like DreamWeaver) to embed the slideshow into one of your pages.
For now, look at the embedding guide for SSP/FL (located here). This guide applies as long as you use loader.swf whenever that guide uses slideshowpro.swf.