I have installed the archicad 26 on my laptop, however when I launch it, it doesn't appear the menu to add a serial number. It opens automatically with my account logged in, in a commercial trial mode. I have an educational license but nowhere to put it...
You can follow this link -started-with-archicad-add-ons. This is a simple tutorial to create an simple Add-ons and add it to the Archicad software.And again if you installed the API Development Kit for the Archicad. In the installation location you will found a folder called "Examples" where you will get some of the demo project for the add-on. I think that will help you a lot.
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