Not at all. No previous Mathematica training is required or expected. Students learn to use the Mathematica code gradually as they progress through the courses. The overwhelming majority (85% as measured by survey) of new C&M students with no previous Mathematica experience report they are comfortable within two weeks.
C&M has brought to me something I thought I would never have-- a bit of understanding of the important relationships in mathematics. Some people (say in my [traditional] calc I class) were able to look at the texts and seem to understand, but I have been frustrated very many times by not being able to. I guess that's why I signed up for this class. I used to not like math. But I was just being a product of the way I was taught.
Techs support both the lab machines and the software used in this program.
In the event of a problem, send an e-mail to tech@cm.math.uiuc.edu.