There are new STEMFIE build plates ready for download from this link. This folder will be regularly updated with new files containing essential components so that you can mass-produce your collection of STEMFIE parts.
Note that all files contain as many parts as possible fitting within a square surface. Most build plates are nested to 140 x 140 mm; if the STEMFIE parts are longer, the 200 x200 mm and 300 x300 mm build plate size are used.
Instead of the STL format, the files are saved as the 3MF format to save space. Your slicing software should be able to import .3mf files.
Enjoy your ready-made build plates and playing with the STEMFIE construction-set toy.