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IIRC the interpretation guide also mentions IT and data security - how relevant this is will depend on the nature of the business and is perhaps less significant if you're small and are using lots of networked production stuff, don't have online access portals for payment or customer/consumer details etc, but it's probably worth documenting that you've considered it either way.
I don't recall it being mentioned explicitly in the standard, but I've included the transport stage in ours too - you can have the most secure facility in the universe, but it's not much use if anyone can tamper with your product between it leaving your site and arriving at your customer 
I'd also document the review criteria/triggers mentioned towards the end of 4.2.1, as if nothing else it's always easier to present direct written evidence to the auditor to show you've considered these things.
4.2.2/4.2.3 will depend to an extent on the outcome of your risk assessment for 4.2.1 - if you have areas requiring consideration then find a manageable way to do it with your small team, but also consider that it is entirely possible to conclude that you do not have any significant threats that need extra controls for management, but I'd document that this is the case if so.
Any sane BRC auditor should approach your site with a sensible expectation of proportionality given the size - having very few people generally makes it somewhat easier to manage direct security than if you're a massive brand/manufacturer with hundreds/thousands of people coming and going from the factory.