Please read these papers carefully the plan and develop the most appropriate user interface for your needs.
Archicad Icon Style Guide (PDF document):The purpose of this document is to list and detail all the rules that we have established for Archicad 20’s new look and to cover how we work when we design icons for the new UI. This document is a handbook for both GRAPHISOFT’s Product Designers and Archicad Add-On manufacturers to help maintain a consistent visual appearance for the icons in our products that we want to reserve in the future.
Documents referenced above do not give technical details. In order to get the information how to control the mentioned interface components through the API please analyze this paper.
There are limitations regarding to the applicable interface solutions. Unfortunately some Archicad standard interface components are not available, or they are limited on usage from add-ons. Please read the details in the paper below.