Application ID

This is a nightmare. We has Fundraising operating and a fundraising event in progress and I updated the Plugin and everything stopped working. Now after much searching and frustration, I can not find any where that you provide a step-by-step to acquire a Application ID. API no problem, but the Application ID is a HUGE form with a whole bunch of fields and no guide to which or how to get one for Fundraising. We are not dead in the water. Help.