I'd assume this thing having been launched in 2005 has enough memory to hold imagery for the entire planet so one wouldn't have to be in the region they want data for. That's my assumption and it seems to agree with the data.
No, these satellites only send out the line of pixels directly below them. For example if the satellite is moving south, your image is rendered from the top down, but from the bottom up if the satellite is northbound.
These satellites are very basic, and that I find is part of the fun.
OK, then in that case I managed to receive the signal from a satellite 800km above but passing over the other side of the planet. How's that explained?
You got a very noisy signal without much information (the gray thing in the background) with an random map overlay generated by wxtoimg. Try to hide the map overlay and you should see the picture you really received.