error mounting truecrypt disk with cryptsetup

cryptsetup expects the sector size to be 512, but in your case it seems to be 4096, since that is what truecrypt does for devices with physical/logical sector size of 4096. This information is stored in the TrueCrypt header, you can also see it with cryptsetup tcryptDump.

The Linux version of truecrypt mounts such containers fine like so:

truecrypt /dev/sdc1 /mnt/somewhere

According to dmsetup it still uses regular encryption regardless of sector size, so this is a limitation of cryptsetup itself. You could open an issue for it on the cryptsetup issue tracker: https://code.google.com/p/cryptsetup/issues/list