Gotta agree with Zellidon. If getting a software to run requires more than double clicking an .exe and pushing Next 3-5 times, you can expect 90% of people to not be able to use it.
Regardless, Zellidon, your entire issue is based upon not having the folder created for mongod. Just go to C:\ and create \data\, inside it \db\ and inside it \journal\ (So it looks like c:\data\db\journal\) abd then mongod.exe and start.bat will load.
If you then manage to open Dashboard but fail to connect to Twitch or open the Configuration Wizard, you'll have to use Robomongo to fix the database.. We'll get to there if that happens. :p
Well that is the thing if you wont follow instructions you wont be able to use it, I explicitly said it may crash and if it does create the folder.
He does not need Robomongo - I asked you to install it because I knew you didnt save the ClientId (or for some reason it didnt save doesnt really matter which one) and we needed to delete the database - I'm implementing workaround for that so if that happens you will be redirected to FTL again.
Even if Zelidon opened mongo and it crashed and then opened start.bat it does not matter start.bat wont do anything because mongo it is not running.
Zelidon problem is that he didnt create the folder. My advice for does of you that have so much problems is always launch any script (not only mine but any app/script) from Start->Run->cmd.exe then cd to the path you want and start the script you want from there, and not by double clicking.
This way cmd window will stay open even if app/script will crash and you can read what is wrong.
Any app/script will throw or show text describing the problem and you can react, if you blindly double click it it will just close in case of problems.
I could include mongodb into the zip and create the folder in C:\data\db for you but come on people it is not rocket science, plus it is 130 MB big, plus I dont know if I can do that since it is external program and I dont know if their license allows it.
To be honest I understand the need for simplicity and people having different computer skills but com on there are only 3 steps:
1. install mongodb
2. run mongod if it closes and it wont stay open you do Start->Run->cmd.exe->cd toThePath->mongodb and you read what is the problem
3. If mongo is running double click start.bat, if it fails to stay open do what you did in mongo step and read the fail message.
I know it might be too complicated for some people but the truth is every notification service out there is already running on a server and people dont need to do any installations, but most of those services are getting money of off it, this software is free and because I wanted you guys to be in control of data flow you need to configure it. It might be complicated but it is how it is.
I might do what people behind Dansgaming notification did and I will configure everything for you, for a price, if there will be need for this (for example using patreon or something like that).
I know it might sound harsh but it is as simplified as it gets - I can do one thing, I can make start.bat to stay open after a failed run and you can read the messages and fix whatever is wrong.