There's no issue with upper left (and everything is parallel/perpendicular). The bit just above my thumb/finger appears to be three layers (though the middle one may be infill) - is quite flexible and have not adhered to one another very well. If the middle one *is* infill, then I believe the setting is on 10% grid. I hope* that's not the issue as I've just fired off another model which is about 11.5 hour runtime (it's a different model so am/was hoping it wouldn't be the same! Also upped that to 20% infill before starting)