Hey, welcome to Quest.
Firstly, with the free version you cannot hide your game code so others can still edit it like you did. It also won't allow you to edit stuff after 30 days. But if you un-install and re-install it, it forgets you already had it so you get another 30 days (though this is kinda naughty).
Secondly, good games are hard to make. You'll learn loads of skills in the process of trying though, and each time you make a game it will be better than the last. You can do everything in QDK you can in hand coding it, though for more complicated stuff it is sometimes easier to see what's happening in the code and faster to type instead of going through a million different windows and having to find the right thing to click (the QDK interface is really good, just that typing will always be faster for some things).
Lastly, I tend to use excel to make maps, as you can make the squares squared shaped then just colour code and add labels to make a map. There are other programs you can use though, such as a paint program for something nice looking and you can get ascii map programs free on the internet too...