The Journey to Elysium - Level 1

First things first. In order to better understand the game and, hopefully, my pointers as well, I am going to start with level one of The Journey to Elysium.

At the beginning of the level you are given the level password. It is at the top right corner of the main illustration:

This is obviously not significant for the very first level, but it can be handy because it allows you to continue the game at a later point.
Note that if you are going for a maximum score you'll probably have to play the game through, level 1 to level 50 - in one go! But, don't attempt to do so before first getting through all the levels at whatever speed. In other words, don't pay attention to the score for now.

I had to do my own difference markers so the Journey to Elysium walkthroughs will show screenshots of the game, featuring my custom-made glowing Xs. Heh.

Level 1 is easy, but anyway... here are the 5 differences between the two images on the first level, called DEPARTURE. Note that level passwords are always all uppercase.