1) The allergen statement is to make you aware that there could be some cross contamination of shellfish during the manufacturing of the food product, however, this doesn't state that it contains shellfish. These statements are required by law on packaging in case of severe allergies. You should be fine, but if you do not feel comfortable or are severely allergic to the smallest amounts then avoid it.
2) The ingredient list is listed in order of weight so the ingredient with the most weight is listed first and so on. We cannot disclose exact percentages as it is a proprietary blend.