Connectors for enclosed outdoor project

[slugrustle]

I'm working on an LED controller board for an outdoor sculpture (scultpure built by someone else). The board will be in a metal enclosure, so no direct contact with weather, but condensation is a concern. One thing I have no idea about: what sorts of connectors are reliable in such an application?

I need to connect up to 48 LEDs to the board with a connector that fits through a 10.1mm diameter hole.
The JST CPT series, which is unsealed, looks good to me: http://www.jst-mfg.com/product/detail_e.php?series=477
The JST JWPF series is sealed and also fits: http://www.jst-mfg.com/product/detail_e.php?series=151, but the board side connectors are top entry only. There is a request to be able to stack multiple driver boards.

I'm also looking to put an SPI flash chip, like the ISL25LP016D, on a removable card. I was planning to use a 10-pin female IDC connector on the removable card to connect it to the driver board. I like that it's polarized and strong enough to support a small board. Are IDC connectors reliable in outdoor applications like this? Is there a better alternative for board-to-board connections?