The Best Answer
Almond milk: It should be fine as long as it's unsweetened. I checked the label and it has no sugar, there's about 1g of carbs from tapioca starch, the rest is fat and protein. There's no artificial sweeteners either. I think almond milk is a yes.
Pumpkin seeds: Yes, it's listed as the #1 food source for magnesium. Nuts/seeds are domino foods, so don't eat more than an ounce or two.
Butternut squash: I'm going to say avoid this one if possible, the glycemic index is the same as a sweet potato or mashed potato, which are not allowed.
The dairy restriction is actually because of lactose, sugar found in milk that your body can easily store as fat if it's not used. Milk has lots of milk sugar, butter has none. Cottage cheese has very little plus it's high in casein (milk protein), which is time-released protein that helps with fat loss. According to the blog, you're still supposed to only have cottage cheese as a 'last resort'.
I agree with KimCo except for the butternut squash.
I've been looking into this myself because I'd rather not do the whole lentil/bean thing. No, not because of gale force winds but because they're increasingly viewed as being "toxic". The paleo style pundits (e.g. the Jaminets, Chris Kresser, etc) say to reduce the grains and legumes because of the toxic elements like lectins they contain. That's the argument against the legumes recommended in Mr Ferris' (excellent) 4 hour body book.
The justification in favour of the butternut squash is that I think the glycemic index is a little misleading by itself. You need to look at the glycemic load, i.e. the GI modified by the concentration of carbs in the food. If you look at www.shaklee.com/pws/library/products/wm_gi_gl_tables.pdf you can see that the GI of butternut squash is 75, which seems high. However, the glycemic load is 10 for a serving of 1 ounce (28g), which is the same as the load for pinto beans.
So, unless there's some empirical evidence that butternut squash prevents weight loss under this program I can't see why it would. I am, therefore, going to proceed with the eatage of pumkin, squash, etc. in the expectation that I'll continue to lose weight and gain six-packs. I'll probably draw the line at potatoes.
I would like to add something to Andrew's excellently detailed response:
You are absolutely right that, according to the paleo/primal (not interchangeable) plans, legumes are for the most part a no-go due to "toxins" (level of toxicity is up for debate). I was primal for about a year and so maintained a no bean diet. I generally didn't eat much butternut squash or sweet potatoes, except for post workout meals where I would exceed 1 hour of training (gotta replenish the muscle glycogen).
However, if the Slow-Carb diet is your plan, then it is best to avoid Butternut squash. Legumes are what makes the Slow carb diet slow. They take loooooong time to digest, and in turn prevent insulin spikes while keeping you full longer. Foods with relatively high glycemic indexes will cause insulin spikes and mess up the rate that you're trying to achieve with your metabolism.
If you're just switching over from a regular high white-carb diet, then even moderate reductions in carb intake will lead to some noticeable fat loss. However, you'll probably get better slow-carb results if you stick to the slow-carb diet accurately.
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