Try without Octo.
Also the two fans on the front of the extruders are controlled by the main board/firmware. You have no control over them. They are to cool the extruder.
The part cooling fan is on the left side of the extruder setup.
Not sure what to call it other than certain versions of S3D are creating problem areas in the model when sliced. See pictures. This is layer 1 of a simple box. Two versions create the spots at the arrows while one other version slices correctly. Versions are indicated in the pictures. This model was...