To use the evaltrace style, simply put the evaltrace option in the documentstyle command, for example:
See the evaltrace documentation for more details.
The "code" style is used for setting code, like verbatim, but still interprets "s̈o that font changes, macro calls, etc. can be made. See the paper sources for examples/
The "cmu-titlepage" style is the standard CMU style for tech reports.