I wear orthotics as well and podiatrist insists I run in neutral shoes as orthotic won't function properly otherwise. However, other forumnites do use orthotics with stability/support shoes so may depend from case to case. On gait analysis, you really need a podiatrist to assess this properly, especially as you already use orthotics and are unsure whether shoe type is correct. There's a lot of clever marketing with treadmills and footscans; however treadmill alters gait anyway and a sales assistant in a running shop is not properly qualified to assess this (some shops do offer links to a podiatrist).