maybe you need enable biolink pages in admin
I already had enabled it before I discovered it wouldn't let me create them. If it's disabled, the button to create isn't there at all. The button was there.
But in the license page, it doesn't have a code or license type. It's a blank field. I checked with another install of this script (back when it was phpbiolinks, so quite old) and the license code (babiato.tech) and type were there.
I found the answer though!
Seems like the code provided here is just source code and it isn't nulled. So I went back in the file history, found v11 Nulled (the latest version that has nulled in the name), which somehow still had a valid upload, installed that, saw that the license info page had some details in, then used the update instructions to copy over the latest files here. Updating the script from v11 DOES retain the license info and I can now use the script normally.
Thank fu** that a download for V11 which I have now saved seperately, was valid. Anyone else who discovers this and has this issue should try this.