There seems to be no english manual around. I found a copy of instructions and programming in dutch language at C-tech. Just download it and put it through Google Translate to read it in english. The pictures might be a bit screwy, but you should be able to read the programming and instructions
http://the-checkout-tech.com/manuals/cashregisters/Sigma_CR-2000_user_and_programming_DUTCH_manual.html
Registerman
July 2011