Be careful with old versions!
These versions are displayed for reference and testing purposes. You should always use the latest version of an add-on.
1) Removed chrome directory
2) Removed chrome.manifest file
3) Removed iconURL and icon64URL declarations from install.rdf file.
Thanks to Leszek Życzkowski (the AMO editor) for the tips
1) install.js removed
2) icon.png is now in the base directory
3) icon64URL added
4) previous project's README.txt removed
5) rename files into hyphens instead of underscores
Thanks to Philip Chee for the head's up