The StudioLive Series III rack mixer SD card recordings functions as a stereo recording of the selected paired sources. So you can record the main mix or a pair of aux mixes etc. It is not a multi track recording function.
If you wish to record a multitrack from the rack mixer you need to use Capture or a Studio One via the USB connection or AVB on compatible Macs.
If you wish to play a Capture session back into the mixer, you will need to use the USB connected and change the channels sources to USB to do this.
Once the SD card is inserted into the rack mixer, the Capture screen will appear to allow you to operate this from an iPad.