Situation: We unintentionally let a financing statement lapse. To perfect again, what is required in addition to a new original UCC-1? Is a new security agreement required, written authorization from the debtor (but not a new security agreement), or can we simply file a new original? The security agreement obviously gave us permission to file a financing statement, but does that cover us for a second original since the first lapsed?

Thanks for any help!

Yes, the security agreement gives you permission to refile. It does not, unfortunately, protect you from any blanket UCCs that may jump your former position.

The security agreement MAY be used to authorize a filing, but it is not the best way to go. If you use the security agreement as the authenticated record that authorizes the filing, you cannot:
[1] File a financing statement before a security agreement is made or a security interest otherwise attaches, as is allowed by 9-502.
[2] Be more broad in you filing then you were in your security agreement, as is authorized by 9-504.