v1.2 fixes an issue in ZecPaperWallet CLI where the system entropy was not being used properly in some circumstances, and the generated paper wallet depended on the user-provided entropy. (This only affects the CLI version of the paper wallet)
If you generated a paper wallet via the CLI and provided weak user entropy, your paper wallet might not be sufficiently secure. You should regenerate your paper wallet and move your funds off of the old paper wallet.