I purchased both Stronghold HD and Stronghold Crusader HD at GoG as of recently --the games are on Steam too! and any tip applies to the Steam version as well.
These games are HD iterations with support for new resolutions and zoom in zoom out, of a game from 2001 (Stronghold HD) and Stronghold Crusader HD (2002).
https://secure.gog.com/game/stronghold
http://www.gog.com/game/stronghold_crusader
Something
important about this game... If you use Windows 7 and Windows 8, you may need a DirectDraw wrapper. This one:
http://bitpatch.com/ddwrapper.html
Then you just have to copy the files to the directory of the game. Then edit the wrapper config file setting the line 'ForceDirectDrawEmulation' to 1 afterwards.
Perhaps you might not need it though. :smile2:
DirectDraw was removed from Windows 8 altogether BUT in my case all I had to do was setting the compatibility settings to Windows XP SP3 and the game worked like a charm.
I used the wrapper at first with Stronghold Crusader HD, but I got both games and when I installed Stronghold HD I forgot to copy and paste the wrapper's files to the directory where I installed the game.
Thing is... I just set the compatibility settings and the game acted exactly as if it had the wrapper installed.
With Windows XP SP3 compatibility settings enabled the behaviour was exactly the same as with the DirectDraw wrapper. The screen blinks and flashes a couple of times and then the game begins normally.
It seems that compatibility mode enables DirectDraw like when it was used.
For those interested in any of those versions and how they do compare here it is a link:
http://www.gog.com/forum/stronghold_series/never_played_a_stronghold_game_are_they_good
The game is pretty cool. Thousands of units on screen at times, 3D like terrain and engine, and the economy doesn't need lots of micromanagement, you just have to focus on defence, basically.
I prefer the original Stronghold HD (had I been forced to say one); it's cheaper, it has a better tutorial, imho, and great campaigns. But if you like the game both versions are totally recommendable.
In fact, I'd recommend both if you fancy the game.