After fixing some notices/warnings, I was quite able to configure and enable this processor on the contribution page.
When using this on a live page, I see an error after like
PHP Fatal error: CRM_Contribute_Form_Contribution_Confirm::preProcess(): The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition "nz_co_fuzion_paystation" of the object you are trying to operate on was loaded _before_ unserialize() gets called or provide a __autoload() function to load the class definition in /Users/jitendra/src/civicrm/CRM/Contribute/Form/Contribution/Confirm.php on line 323
I think as it doesn't actually follows the hierarchy CRM/Core/Payment/... this error is thrown.
$this->paymentProcessor['object'] has a class named
__PHP_Incomplete_Class though it contains the paystation object.
I cloned it from https://github.com/eileenmcnaughton/nz.co.fuzion.paystation