Ashley, I think it's actually possible to set achievements using the Steam Web API -- i just heard back from someone at Valve who posted this:
[quote:3lqf3kps]Caveat: I don't know anything about Node-Webkit, Construct 2 or Greenworks.
The Steam API is a REST API, so if you know how to call any other REST API, you should be able to interact with the Steam Web API in the same way. Just need to pass the Web API key for your app.
If you haven't already viewed the list of available functions, use http://api.steampowered.com/ISteamWebAP ... =json&key={replacewithyourkeyhere} and that'll give you back everything you can call.
E.g. SetUserStatsForGame should let you set the achievement (by steamed, appid, name of achievement, etc.). GetPlayerAchievements will give you the achievements for a player, etc.
I checked the url he provided and entered the Publisher API key I created in the 'groups' section of the Steamworks partner site and lo and behold theres a mega list including a butt tonne of Steam functions available....
My heart is beating wildly... Can this be used to build a Construct 2 plugin to post stuff to Steam? I can honestly say if someone built the initial plugin to post say a high score, i could likely figure out the rest and get the other steam functions done up myself, ASAP style.