I can't find any way to access an editor or have replays, but both features are advertised on the game's store page. The "Truck Cannon" mentioned also doesn't seem to exist in the game. Also, is there any way to view my own high scores? The high score table at the end of each level doesn't display any information, and it would be nice if I could at least try to beat my own records.

EDIT: It seems that these features, despite being advertised on the store page, simply aren't present in the GOG version at this time.

The truck cannon does exist in game, it's a utility called "Portable Truck". There is nothing advertised on the store page that is not present in the GOG version of the game.
It is a shame though that you cannot at least see your own high scores - I'm thinking of buying it twice over on Steam, so that I can compete on the leaderboards, and play the workshop maps.
The game is actually more expensive on GOG than on Steam, and it doesn't even include the same features that give the game replayability.

Not anymore, but that's because GOG silently changed the game's feature list after I brought attention to it. Attached is a screenshot of the original feature list, which mentioned the editor and replays, neither of which exist in the GOG version.

My apologies then. I bought the game as soon as it was released on GOG, but I didn't bother to look at the description, I just assumed it would have the same features as the Steam version; minus the Steam workshop of course. Let's hope the GOG version will be improved.

Sorry but I don't see it. They seemed happy enough to knowingly sell a game with missing features for 20 AUD and then try to slide that fact under the rug.

I wouldn't bet on the developer reading this thread either (apart from trying to cover their own asses) and the forum they DO read is steam, so if you ask for anything related to "drm-free" or have a severe problem with a game you'll get swarmed with posts from angry children.

Hell, the system is downright broken. You beat a level and then see a completely empty leaderboard with not even your own time on it.

Sorry to be a downer but the track record of devs doing this and then going back and fixing it isn't good.

That's a downer; I almost bought this game.

Eh, I guess I'll wait until they add these things and, if not, I just won't buy it.

The Linux version on Steam is drm-free, too. However, it is probably not what you expect. When started outside Steam, all online features including the level editor and highscore tables are disabled and don't even show up in the menu either.