I am not sure where is the problem, if you have successfully configured it for 5 seconds just replace the time expression to the new one. Here you can find how to configure timer expressions and what is supported.
For the docs
Adrian Alonso wrote:
You should use this one as it referrers to jBPM 4 the other one is describing usage of jBPM 3.x as that one is part of the SOA platform (Red Hat product)