Does anyone know of a PNG National Rail Map with reasonable file size?

[ccityplanner12]

I am trying to make a map to show all the lines I have been on. I have downloaded the Project Mapping blue lines map & converted it to PNG, but MS Paint is not liking its large file size (52.1MB). Is there a map I could use that shows all lines & stations that has a smaller size when in PNG?

 

[_toommm_]

You could always download GIMP - it's a much more versatile tool (alongside being free) and it handles the file sizes easy.

That's what I use for my map showing what lines I have done anyway.