This may be a no-brainer for many Tiny Core users, but I can confirm that this will also work with LUKS encrypted volumes using the same instructions but substituting the command:

echo -e “#!/bin/sh\nsleep 1\n/usr/local/sbin/cryptsetup luksOpen /dev/md127 raid5crypt –key-file=/mnt/sdd1/pre/test\nsleep 1” > $DIR/$PKG

I'd be happy to update the article, but thought I'd get some input first.

Note: I was not able to make it work with a passphrase…I would never see a prompt during boot. Works fine using a key file though.