>>6850608>has anyone had terrible warping on airfix kits latelyNo, but most of the 1/72 "new tooled" airfix kits I have I purchased soon after they came out. Did notice that, like you I had a small gap down the middle of the fuselage after the two halves went to together that needed filling.
Next time, take masking tape and mask off the gap, so you will only have a little line of putty that is only slightly bigger than the gap itself. It will be much easier to sand and re-scribe the horizontal lines that way.