Just again talking about my personal experience:
The first attemp to install code::blocks on Ubuntu, I download the files as wiki say, but, when I run codeblocks, and set the projectname, i receive the same message in /home/codes, I tried checking the permisions and everything you write up, and I can work when uses my personal directory to create the projects, I mean, the proyect directory that I use is /home/xbit/codes, that way I can work fine, so, try it. Good luck!