E:Can't mount / cache/recovery/command/
E:Can't mount / cache/recovery/log/
E:Can't open / cache/recovery/log/
E:Can't mount / cache/recovery/last_log/
E:Can't open / cache/recovery/last_log/
failed to open/sys/class/android_usb/state: No such file or directory
This is actually an extremely common issue it seems. Basically its' quite likely you're partition map has some how been damaged.
Firstly just make sure you can't install an update or restore an old backup from SD, if that still fails and you end up straight back in CWM
All you need to do is download the parted binary HERE extract it from the archive and push it to your device or even just put it on an SD
ADB into your device and run the binary with the following command (you'll need it to be the accesible path or you can just be in the directory where it is)
parted /dev/block/mmcblk0 print
It will most likely show up with an error and ask if you want to fix it. Just say yes and let it do its' thing.
After it completes, reboot your device and see if you still get the same errors, Attempt to install CM7 once more.
If it still doesn't work, run the parted command again then download Adams total wipe and run that. It'll reset your device back to total stock. The parted command will repair the partition table and adamoutlers software will upload all the required software to the correct places for it all to work
Hope that helps!
If you get stuck feel free to give me a shout