Are there postures/techniques in Yiquan based on the I Ching?

Never had personal study in it, but have Sawais' book and other references. Seems like he left out almost all of the items of that nature and just stayed with simple functional movements.

No.

Are there five element practices in your style Tim? Thanks for the answers

The first five forms are named after the Five Elements (arbitrarily).

What does your Yiquan curriculum consist of?

There are seven major categories of practice in Yiquan: holding static stances, power testing movements, footwork, breath training, power issuing, fixed partner sensitivity training and sparring.