If you place a part next to another that can connect to it, you get a free connection. Examples include: Boilers + Engines, and Levers + Engines. This way, you do not have to hunt down Bakelite for cables or Iron for pipes before you make your first contraption.
A turret will only fire when you click if you are clicking within its firing arc. This can be useful to prevent you from shooting yourself.
There are a few resources, such as Azurite, which are only for coloring parts. If you don’t care about aesthetics, you can dump them to make some room.
You *can* hold the mouse button to continuously fire your turrets. Just keep in mind that for some enemies which move around abruptly, you might be better off taking your time with each shot.
The flax plants in the Oasis will not attack the player, only their contraptions.