Hello and welcome @Ludwig !
Firstly I hope that your grandchilden legs are at least 75 cm long otherwise they won't be able to reach the pedals 😉 (short fork)
Currently we do not have any pro supplier for the wood kits anymore (@zophon ?), I will look for a new one asap…
Alternatively the 2 step files are prepared for 2x 0,5x1m² 19mm 3-ply A/B quality spruce form tilly.at (only supplier ensuring the mechanical properties of this product).
The MAD is a group of different craftsmens in france working together, they are our official fork suppliers 🙂
No problem with you questions, do not hesitate to rename this thread into something like "Ludwig moskitOS" and continue asking your questions on it.
It is always good to have people interested also outside France 😉