A multi-OTR system (4 beam ellipse diagnostic devices based on Optical Transition Radiation) was installed in the extraction line of ATF2 and has been fully operational since September 2011. The OTRs have been upgraded with a motorized zoom-control lens system to improve beam finding and accommodate different beam sizes. The system is being used routinely for beam size and emittance measurements as well as coupling correction. In this paper we present measurements performed during the winter run of 2011 and the early 2012 runs. We show the reconstruction of twiss parameters and emittance, discuss the reliability of the OTR system and show comparisons with simulations. We also present new work to calculate all 4 coupling terms and form the 4-D intrinsic emittance of the beam utilizing all the information available from the 2-D beam profile images. We also show details and experimental results for performing a single-shot automated coupling correction. Show Partial Abstract