Theme isn’t tested with Google Webmaster tools but as I can see your issues can be fixed with few adjustments.
– You can change font size in Theme options.
– Viewport is configured by default so I am not sure why this error appears. If you delete it please check in
– Touch elements too close issue – not sure for what element is problem in this case, I see in second file link to jplayer which is audio player. Audio player has it’s own skin and it’s not easy to change it but you can play with CSS if you have some time.