Nope. There are no goal requirements and no deadlines when you use CrowdRise for your fundraising.
Setting a goal is a great idea and we do recommend it. Reason being, it's great to have a target (you can always reset it if you reach it) to talk about with your supporters.
It gives you a chance to reach out and let them know when you hit milestones, how close you are, and we have definitely found that communicating with your supporters regularly leads to more momentum and more repeat donors.
All that being said, if you do set a goal and don't hit it, you still keep all the money you raised. For real.
Also, there are no deadline requirements. You can definitely set an arbitrary deadline which does the same for your fundraiser that a goal does... give you a reason to talk about how many days are left, create momentum, etc.
On CrowdRise, your fundraiser lives forever and you can continue to keep raising money even after your fundraiser is 'over' as long as the DONATE button stays active. That's one of the great things about CrowdRise - your philanthropic efforts can live forever. So awesome.