here the way it work , I make it work on openvpn 2.5 and openvpn GUI support script but you can use up command to make it work the same way . it is on both windows 10 and new openvpn 3.0 make it trouble so carefully will make it work as you like.
the trick in here is make the first scripts finish first so openvpn network card have ip address then the first scripts will call other scritp to create network map for you. if you try to make it work on the first scripts it will never do for you.
https://forums.openvpn.net/viewtopic.php?f=8&t=32636