I think I picked up the SH5 hardcopy for about $10, would def recommend going that way; last time I checked TDW's fixes weren't compatable with the steam dowload though that may have changed.
THfRO- based on the book; was that circa 1987? I had it on my Amstrad PC1512, with a monochrome monitor!
Good your getting in to SH4, when you get to 194* (oops I forget the year
) I can help you get the option for dual deck guns working properly
, and If ya get bored I also have a playable Iowa mod from an unknown auther too.