Does anyone know how to take that nw.exe file and make it something that looks more finished instead of having it buried in a file? Is there an easier way to make the EXE accessible?
You mean like an installer? Try Inno Setup - jrsoftware.org/isinfo.php
And finally has anyone published on Steam? What are the next steps I would need to take to prepare it to publish it?
There aren't really any special steps you need to take to prepare your exported files, they will work as is for Windows on Steam. Linux there is an extra file needed not included in the export, don't know about for Mac.
As for getting it on Steam, basic steps are:
- Sign up as a Steamworks partner (https://partner.steamgames.com/). You will need tax, business and bank details to set up fully
- Purchase your appID for 100USD
- Set up your Steam Store page with info and images (requires approval)
- Download the Steamworks SDK and use that to upload your build
Build will need approval before release,which is mostly just checking it works and matches the store decription
There is documentation and a developer forum available once you've signed up.
If you want your game to be successful on Steam, you'll need to look into marketing and promotion.