Ok so after cooking up a mod I tested it out in single-player and noticed a mistake that I made. I fixed the mistake, reloaded the mod to steam, went back into single-player, pressed the Refresh Mods button, and tried it again. Well, it seems that the game is still running the original version of the mod. So, how do I get it to use the newest version?
exit steam then re-launch to download the latest version
Well crikey I think that did the trick. Thanks mate!