Random Forest Example: trouble getting Describe to work

Currently I'm trying to follow the Random Forest example on the website(
https://mahout.apache.org/users/stuff/partial-implementation.html).

When I try to run Describe data I get this error:
[values missing for attribute 1]
Error here: http://pastebin.com/QGCCqvc5

It seems like the possible values for categorical aren't there, so I tried
it ignoring all categorical attributes, then I got a null pointer exception

Error here: http://pastebin.com/56AEKhse

I'm wanting to use this with my own data set, and I'm getting the same
errors with my data.

Can anyone advise if I'm doing something wrong, or if there's a workaround
I should be using?

Thank you,
Jessie