No information is necessary to register for a Mycelium-Coinapult Lock Account.
You can provide an email address to be associated with your account, but this is completely optional. Please note: this email address cannot be the same email address of your Coinapult Web Account. The two accounts are treated separately. (It is not currently possible to link your Coinapult Web Account and your Mycelium-Coinapult Lock Account, but this is a feature that may be added in the future.)