It worked fine for me. What and where exactly are you changing the title and meta description?
On the pages when editing them, under the Wordpress SEO options.
When I make a change to the Title, it's not saving it. Well, it's making the change in the Source file but when you go back to edit the page, the title area on the SEO Wordpress options has defaulted to the original title. Very strange. For example, I want the title of the page (in the Wordpress backend) to be "Services" however, I want the title bar to show a short list of the services offered. I could rename the page to the long Title I want, then change it in my menu bar to show "Services" but I don't think the customer will understand that they need to do all those extra steps. I also don't want that long title to show on the page, which it would if I tried that workaround.
The description was just not where I expected it to be, I did a search of the source code & found it.
What would be the value of using this plugin versus the SEO in Atahualpa?
I have never used the Ata SEO options, I was using All In One SEO before I started using this theme, so It's what I stuck with.
I wanted to use this SEO Plugin for a clients site, because it is very visual. It shows the how a google search result might look for a particular keyword. And it should help to focus the page to a set keyword or phrase. It also offers related keywords suggestion tool.
I'm not sure if running WP in a subfolder is causing the problem, I don't know if that may be an issue or not, but it's caused other little quirks with other plugins.