Welcome to Lantus Land!
It looks like you had posted on the main, Health board. Here's your
initial post so people stopping by can get up to speed.
A quick question first: How much of Humulin N were your giving?
Are you giving a shot twice a day or once a day? From Doogle's spreadsheet (SS) -- and great job getting it set up so quickly -- it looks like you are giving 2.0u once a day. In cats, Lantus is dosed twice a day. (In humans, it's a once a day shot but a cat's metabolism is about twice as fast as a human's.) If you are shooting twice a day, the dose goes in the "U" column (it stands for units) that is next to both the AMPS and PMPS columns. It's the columns that are in turquoise. If you are, in fact shooting once a day, I'd encourage you to consider shooting 1.0u twice a day, every 12 hours. Pick a time that works for your schedule.
Just so you are aware, if you use the Tight Regulation (TR) Protocol or if you decide that you prefer the Start Low Go Slow (SLGS) approach, you are more than welcome to post here. There are several people who are using SLGS and post on this Board. The TR board is big and we're busy. There's usually someone around almost 24/7 since we have members from all over the world who post here. It's rare that you would have to wait very long if you were in need of help or had a question. You don't need to make a firm commitment to which protocol you use right now. (Just remind us if you decide that you want to use SLGS since most people here do follow TR.)
If you haven't done so already, please take a look at the starred, sticky notes at the top of the board. There are significant differences between Humulin N and Lantus. It's going to take a bit of an adjustment to think about dosing that's based on nadir rather than pre-shot numbers. You'll also get far better duration from Lantus than from N and, as a result, you'll hopefully see less of a swing in Doogle's numbers by the end of the cycle. It also takes up to a week for Doogle's system to build an insulin depot. This is very different than N which is quick in and out of the system. Lantus builds up in the cat's system so that doses act in a cumulative manner and so you have overlap between doses. This is one of the big advantages of a long-acting type of insulin like Lantus.
Please let us know how we can help. The people here are wonderful and very generous with their time and their information, to say nothing of their support. I hope you'll post regularly and find a "home" in this community.