The additional parameters field is for anything else you want to stick on the web2lrf command line that I didn't include an option for.
For example, I didn't include an option for keeping the downloaded files, but you can stick this:
Code:
--keep-downloaded-files
into the additional parameter field and it will be added as is to the command line.
I did a quick update over lunch; I forgot to update the version number in a few places so I fixed a few small bugs, updated the localization text, and updated as 0.2.5.