Line breaks in the user's biography are, by default, stripped out by the WordPress
wp_filter_kses filter. This is in item 7 in the FAQ. Adding the following to your theme's
... should allow line breaks to be honoured. This might be a configurable feature in the plugin at some point in the future.
The issue you've seen where the CSS doesn't resize in line with the avatar image has been fixed and will be in v2.2 of the plugin which should be released this week.
As GMail is a web-app running inside a browser, most operating systems don't support URL schemes such as
mailto for handlers inside web-apps, which is why you're seeing this not work as you might expect. But there's a work-around to allow this; see http://support.google.com/mail/bin/answer.py?hl=en&answer=10966
I've never come across the Genesis Featured Widget plugin and as Genesis is a premium theme (in other words, I'd have to pay to be able to test this), plugin clashes or unexpected behaviour are really difficult to test out. But I'll have a look at the plugin's code and see if there's anything immediately apparent. Would you be willing to try testing some beta code if I am able to work out what's going on?