Please upgrade to 1.6.1, available on my website.

Your username and password for your FTP are different than for you Google account. This is one of the most common questions asked and it is stated right in the readme.txt file. I'll upload 1.5.3a (less bugs than 1.5.3) to the downloads section today, but I am now hosting all of my updates on my site only and therefore is the only place to get 1.6.1.