Order Preserving Encryption for Numeric Data Values
To answer your second question, Paillier and other CPA-secure homomorphic encryption schemes cannot provide order-preserving encryption. The security of these schemes rely on using a random factor during encryption to ensure their ciphertexts are distributed randomly in the ciphertext space. OPE must use a weaker notion of security than CPA. 

In terms of your first question, I don't know enough about the data structure behind OPE to follow what you are asking. I know OPE is an available option in CryptDB so maybe they have automated the process of defining the limits you are asking about?