Hi and welcome to Just answer.
Initially, in able to use windows 8 on your Pfaff 7570 you need to upgrade your software to 6d. This is expensive software to upgrade.
Practically, I would suggest to my customers here that they buy a old pc with windows xp just to dedicate to the machine. Windows xp is the best for your 7570 creative software. Windows xp laptop is cheaper compare to very expensive upgrade.
Hope this information will be helpful.
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