Couple of problems on the signup page

Hi,

I have a couple of issues with the signup page.

Firstly, I entered the information below, and the error at the top reads 'Only lowercase number and letters allowed' - but the name I entered was all in lowercase.

Also, on that, is it possible to change the font colour of the error messages, as it took me a while to realise there were any errors, as they don't stand out, and it was pretty frustrating until I realised about the errors!

Secondly, I would like to make the 'signup_blog_url' box smaller, so the http://, the box, and the .4.biz are all on one line. See below.

Thanks!