Here’s a quick reply because I’m a bit bleary-eyed!
Red horizontal line – there seems to be crowding at the foramen magnum (opening at the bottom of your skull) where the lower part of the hind brain (cerebellar tonsils) sits within the opening, where it should sit 5mm above this.
Blue vertical line – I think this distance looks a little long, between the back of the skull and C1 – I maybe need to look at that more.
Green vertical line – there is loss of lordosis (the normal ‘c’ shape of the spine) in the upper cervical vertebrae, from C4 upwards
Pink vertical line – there is some anterolisthesis (forwards slippage) of C4 on C5, it’s less than 25% therefore grade 1.
Purple vertical line – this could just be an artifact or, if it’s not, depending on your age, this could just be the central canal of the spinal cord, or this could possibly be the beginning of a syrinx
Orange vertical line – there seems to be some contact here (maybe) of the spinal cord, with the back of the spinal canal wall, with additional pressure from the back of C2 and C3. The spinal cord maybe aggravated by movement or position, this could irritate the cord and cause intermittent or persistant symptoms.
Turquoise horizontal line – or more to the point below the turquoise line, where we’ve lost the centre of the cord, could indicate a degree of scoliosis.