Using addwitnessaddress with one of the newly derived addresses (with the "legacy" private keys) returns an error because "segregated witness is not enabled on the network"
Is that actually the case or is it just a parameter I need to change? Has anyone actually claimed forked coins from such addresses?
Is your wallet fully synchronised? That's normally what causes the issue of it not being enabled on the network yet (as you haven't gotten up to that block so core doesn't know it's been activated).
Right... I imported the first address and took about 15 minutes to rescan the whole thing. Since it doesn't give me an option to add all my addresses and add witness address beforehand, I thought I could be clever and do it on an empty blockchain wallet, then take the wallet dat to the synced client. But no... it has to give me grief
This whole thing proved more trouble than it's worth but I'll give it one more chance to see it to the end. I should be very close now.