To quote the zuluCrypt dev:
"I think the problem is due to zuluCrypt being build while installed version of cryptsetup was less than 2.0.0.
cryptsetup 2.0.0 is a major update and they changed the library name from “libcryptsetup.so.4” to “libcryptsetup.so.12”
The solution is to simply rebuild zuluCrypt with the updated library. Did you build zuluCrypt from sources or you obtained it from your distro’s repositories? If the former then rebuild zuluCrypt and the problem will go away. If the latter then make a bug report against your distribution and ask them to rebuild zuluCrypt."