If you want to play sp with plugy here's what worked for me: install D2SE, download median -> proceed as readme.txt tells you. After you do that run D2SE as admin and with compatibility with windows 7 (i have windows 10). No issues after that.
PS: I got the game running with plugy without d2se, but it was crashing when doing save and exit randomly when playing.
TSW shouldn't be an issue. Just use launcher when servers are ready (35minutes from now)