Comment Your biggest problem isn't humidity... (Score 3, Insightful) 249
Your biggest problem isn't humidity, it's going to be salt. Those cargo containers are not airtight, and if nothing else your crates and pallets may be sitting on a dock for an extended period of time. If things are in well-sealed cardboard boxes, it shouldn't be an issue... but you're not very clear on how your stuff is being packed.
Consider getting one of the large rolls of cling-film used for shipping (i.e. similar to saran-wrap). For electronics (TV, computer, printer, maybe even the coffee machine) wrap them individually with the cling-film; it's not perfect, but if done well (i.e. tightly and completely) that should choke-off any salt spray from finding it's way inside.
Also, anything that is on a pallet (but not a crate) should be wrapped and strapped so that the (a) the pallet stays in one piece, and (b) it is tamper-evident.