w1 core mechanics is that u can only build someting near the roads (and make the new roads itself too)
and i cannot remake this now with triggers or plugins
the only way i can think is to reuse walls somehow
so when remaking w1 u have those options
1) not make this mechanics at all and just play like w2 style (not depending on roads or anyting)
2) make it very cursed and fucked up way (that prob will be very buggy anyways)
p.s. and even if u somehow maked it that player can use them normally and they work like in w1, u will be still need to teach AI to use them properly, and its very fucked up and cursed X5 by itself