The class file badly redefines
\year, which is a TeX macro for the current year, and is used by
pgf to set a random number seed when it loads.
Changing the order of loading the packages, as Peter Grill suggests, will fix the MWE but other issues may still be present.
In the following, use
\setyear instead of
\year from the class:
You should probably also do something similar for
If you are able to tell the University to fix their class file, then Scott H.'s answer is preferable (with a
\mymonth as well).