I do have a knitting machine, and have been using it right now to practice with before knitting anything. My problem is that when I do knit in the stockinete way on the machine, and do only plain knitting, as I am a beginner at this, the little blanket I make does roll up. Crocheting around the edges does not help at all.
That is a characteristic of stockinette stitch - the edges will definitely roll up. Hand knitters typically start with a few rows of garter stitch or similar stitch that lays flat and also will work a few stitches on the edges in garter stitch to minimize the effect. On the knitting machine you can achieve the same effect by reworking stitches by hand after they have been knit by the machine. For garter stitch for example, you would rework stitches in every other row to be a knit facing you instead of a purl facing you. This is not hard to do with your latch tool. Does this help at all? Sometimes also, wet blocking or steaming the fabric will remove most of the curl.