I think you are not priming the stove long enough for the volume of of alcohol you are using. Try a priming pan underneath (cut down cat food can) with a few drops of alcohol or wrap a wick around the stove body with a few drops there. I think it will work better than the pre-heat method.

On the trail I prime from the top (my filler hole is sealed with a screw or a penny) but I sometimes use a few bits of "fire starter material" (wax mixed with lint and saw dust) along the side of the stove to guaranty a good start.

Use a windscreen. It not only blocks the wind but radiates heat back to the stove.

You didn't say how much fuel you poured into the stove. Only use an ounce to start. If you add more than that it will take to much heat to vaporize the liquid alcohol.

Try it without the inside insulation as well.

There are a lot of variables with such a simple stove. You can really personalize them.