Mike Marcelais has just submitted some Achievement Flag Info for
Gunpowder (Windows):
You can view the flags they submitted here:
Flag submission by Mike Marcelais for Gunpowder (Win 8)Mike Marcelais said:No multiplayer play. No achievements are missable since you can replay any level you want at any time.
There is a general bug where if you unlock an achievement while playing the trial and later go and buy the full game, you don't get credit for those achievements. The developer is working on the issue. This could affect several achievements, but the bug is not specific to any specific achievement (so I haven't tagged any of them as buggy).
[The achievements that could be unlocked during the trial are:
Breaker's Dozen, Cactucide, Collateral Damage, Nothing to Lose, Oops, Parting Gift, Sweep the Keg, Time Sublime.]