We've had a group of students from last semester who had some trouble with code.google.com hosting.
So I wanted to share with you everything that we learned from that, so that you could benefit as well.
I actually talked about it very shortly in the last meeting but i want to repeat for those who weren't there or for those who didn't hear or understand.
The thing is, code.google.com allows for two types of file hosting. One is static files (served from yourproject.code.google.com/files/…) and one is through a source control system called SVN (or SubVersion).
Please do NOT use the static files for your gadgets but only SVN (if you choose to work with code.google.com at all. Note that this is absolutely not required, and hosting on the GGE or on googlepages or on your own server or on the university is great too).
If you use static files hosting you CANNOT DELETE OR MODIFY your files after they have been downloaded a few times. And this means you cannot change the gadget, like fix bugs, or add features.
So again, if you use code.google.com hosting, please use only the svn mode.