Problem installing Fuel

Hi,
i am trying to install FUEL on my Ubuntu 10 box.
I am facing couple of issues.
1) Problem making fuel/application/cache and other directories writable.
I am doing a :

sudo chmod 755 -R PATH_TO_FUEL/fuel/application/cache
I changes permission on PATH_TO_FUEL/fuel/application/cache directory, but, not child directories.

When I try to access fuel admin, I get strange error :

A PHP Error was encountered

Severity: Warning

Message: require_once(base_module_model.php): failed to open stream: No such file or directory

Filename: models/users_model.php

Line Number: 3
Fatal error: require_once(): Failed opening required 'base_module_model.php' (include_path='.:/usr/share/php:/usr/share/pear:/usr/share/ZF/library:/usr/share/ZF/extras/library') in ª.!ª(!“(! on line 3 Call Stack: 0.0002 327540 1. {main}() PATH_TO_FUEL/index.php:0 0.0006 329032 2. require_once('ãå,/PATH_TO_FUEL/fuel/codeigniter/core/CodeIgniter.php') PATH_TO_FUEL/index.php:236 0.0109 544260 3. Login->__construct() PATH_TO_FUEL/fuel/application/../modules/user_guide/:267 0.0269 1002572 4. Fuel_Loader->module_model() PATH_TO_FUEL/fuel/modules/fuel/controllers/login.php:28 0.0269 1002660 5. Fuel_Loader->model() PATH_TO_FUEL/fuel/application/third_party/fuel/Loader.php:107 0.0337 1469404 6. Modules::load_file() PATH_TO_FUEL/fuel/application/third_party/fuel/Loader.php:237 0.0338 1482504 7. include_once('_ö,/PATH_TO_FUEL/fuel/modules/fuel/models/users_model.php') PATH_TO_FUEL/fuel/application/third_party/MX/Modules.php:142
Please, help me to fix the problem.

Thanks in advance.
Ravish