The codes to reproduce some of the figures displayed on the use cases and in the corresponding paper are available via https://github.com/jkeune/ERA5-DROUGHT_data.
In addition, as part of ECMWF's Code4Earth challenge (see https://codeforearth.ecmwf.int for details), an interactive jupyter book with detailed information on the data and drought storylines with visualisations that explore and explain this drought data set is being developed: https://ecmwfcode4earth.github.io/tales-of-drought/.