The attached was put together in response to the posting by Andrew Hartnett. It contains a bare-metal IAR project for 9-axis sensor fusion V7.00 on the KL25Z. You need to have built KSDK for the KL25Z to include the ISSDK option. Then unzip this file into your SDK_2.0_FRDM-KL25Z/boards directory. The sample project is then located at SDK_2.0_FRDM-KL25Z/boards/frdmkl25z_virtual_shield/issdk_examples/algorithms/sensorfusion/baremetal_sensor_fusion/iar.
There is also an included freertos_sensor_fusion project. Ignore that for now. It compiles and links, but needs more RAM than the KL25Z supplies. I'm looking at ways to decrease the RAM requirements to fit.