it means you have permission to release the submission in an altered form - be it by porting to another platform (e.g. porting a visual style to a mac or linux theme) or by modifying it from its original state.
if such permissions are not stated at the release site then you must contact the author should you wish to release a port or mod.
I think the "ports and mods are allowed" is just too generic and vague, meaning the ocasional visitor could take it, modified it a little and sell it. Maybe a link from that statment to a detailed page with what excatly means could solve it, you know, for legal reason. And while I am this, a copyright statement on each piece wouldn´t hurt anybody and help a lot.
I became more worried about this when I found a wallpaper made by me, in some random website, used as background as it was made by the person. The guy/girl didn´t cared to answer me mail and the website where this blog was hosted, of course didn´t answered either.
I agree, its definitely something we wanted to address so thanks for bringing this up ikonoclast. I also think Creative Commons is the way to go. This license in particular for ports/mods: http://creativecommons.org/licenses/by-nc/3.0/
It seems to me that there is no way to separate ports from mods using CC -- they are both simply modifications. I know a bunch of submissions allow ports but not mods... so to those authors, is lumping them together okay?
