Well, I was able to mount the shares from my other XP machine, but this one's a real relic (windows 98SE). Quite a few in the shop here to use. All good.
I saw something somewhere about umask=0,0,0 but I don't know how to deploy that line. Also an exfat parameter. These are for the fstabs file. But it was for an older version of linux.
I get the expected "host is down" error 112.
It's not.
I'm running raspian with all of the updates (250MB) and samba tools and all. Using the RPi B+