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So here is a site that I notice uses what I am referring to...https://www.starfiredirect.com

Go to the very bottom of the home page and notice the red bar, click it.  It just shows additional information and testimonials.  This site is ranking very well and very fast for popular phrases.  I have been trying to study what they do, and have noticed this little trick.

I have seen several sites that put a div feature at the bottom of a page to hide content.  If you click on the button, it will extend the page down and be loaded with paragraphs of text rich with keywords.

Does anyone know is this is viewed as a negative with Google?

Changing your site template should not have effected your page rank.  Matt Cutts from Google explains that page rank is a formula based on backlinks and the quality of them.

I wouldn't stress too much about your PR.  What matters the most is how well you are ranking.  If you haven't dropped in your keyword rankings, then you have not been sandboxed.  Just continue to focus on building quality backlinks.  Build your PR back up.

Brian-

No worries man.  Even though your site doesn't have the coveted high PR yet, Google is fully aware of what you are doing and what is linked to you.  I have seen sites go from PR0 to a PR4 over night just because it happened to be the day they released all the new PRs.  Don't stress at all about it.  Just keep focusing on good SEO practice.  You'll get there before long.