The CL44 doesn't have separate 1/4in. inputs and outputs. It utilizes XLR input and output OR a TRS input/output.

Typical hookup to a mixer is to use a TRS to TRS cable connected from the boards Insert to the single, blue, unlabeled, TRS input/output on each channel of the CL44.

The plug labeled Insert on the CL44 is for the input/output of the compressor sidechain.