As far as I know, if I set write permission to a directory (+w), I will be able to copy files inside and the execution permission to a directory (+x) allows me to list the content of it.
I get problems when I set /root directory with rwx----w- permissions (702), and try to copy a file inside. I get and error that says something like:
cp: cannot perform 'stat' on '/root/myfile': Permission denied
Why does this fail?