Is it okay to charge for a software created during a uni project? Disclaimer: I'm not entirely sure whether this is on topic for this SE site, but it seemed the most fitting.

Prequisites:
In our masters programme in Computer Science, doing project work is mandatory and we get credits for it that count towards our degree. The projects are of different nature, most are more on the research and experiment side, but some are "commissioned" by companies, who can pitch a topic to the supervising professor and the professor can then choose to accept this as a semester project. We're in Germany, if that's relevant, and no contracts on the topic have been signed, neither with the company nor with the university.

The situation:
Over the course of the past semester, me and five other people have created a website for a company on the grounds of that software project. While the company had input (defining the goals, tools to use, giving feedback, etc.), all code has been written by us, without any "teaching" input from the company. The company now wants to launch the product we created, and is looking to get quite the revenue from it. 

While we knew from the beginning that they would probably launch the website and make profit of it, we also assumed that we would be in some way compensated for our work that we - essentially - did for free, should the project actually launch into production.

However, in a discussion today, our sorta supervisor was a bit baffled today when we brought up that we would still need to talk about usage rights. He also seems to not be very knowledgable on the topic.

The question:
Is it generally considered okay for us to request compensation for our work, and withhold the transfer of usage rights should the company not agree to pay us? We're of course not looking to be paid significant amounts, seeing as it was a uni project after all, but we have created a product that can be launched to production as is, which will generate them at least some revenue.
You'd have to check the case of your specific school and country. At least here in Chile, by law everything a student creates as part of their classes belongs to the school.

Sure, they'll probably be generous in their relation with you, but you must at very least talk to them.