I stopped with the introduction right when it was starting to get interesting and the main character was about to take shape.
It's going to be a robot - with a rough size of 48x48px on a 1024x768px screen - some ratios to keep in mind when adding detail to your designs. There simple is not enough space on a small pixel canvas to show all the fancy things we can do in Inkscape.
I did alter (update) the design of the tutorials a little bit to show more of the object we are working on and also to allow zooming in and uploading the images in 2x the size.
It's helpful to know what we are actually getting out of inkscape at the end. Select the inner boundry box [remember to unlock the layer first] and the character and export them with File/ Export PNG Image and selecting the 'Selection'. You can set the pixel size right here and in the case of the robot the 48x48px result looks like this: