As for following the style of handwriting by writing it in Kufic script, no Muslim holds this to be obligatory. Likewise, following its use of the letters wāw and alif is a fine way of reproducing the wording in the Companions’ written form.

As for declaring someone a disbeliever for writing the words of the Quran in the script he ordinarily uses, I know of no one who has held that doing so makes him a disbeliever. However, following their script is better. This is what has been reported from Mālik and others. And Allah knows best.