ok, demonstration of what can be done (not based on symph map per se, uses 8880 cell size which makes it bigger a bit but then leaves me with no clue as to what the scale is):
Everything with a color has a 32-transparency color overlay. Western Europe is done with solid color outline with a size 7, 255 softness outline (using a Paint.NET plugin). Central Europe and Italy are done with size 5, 254 softness outline, no solid outline (same plugin). Eastern Europe is a mix of both: it has a solid outline and uses Central European outline settings.
Data for the rivers (127 transparency) were taken from the rather wonky CIA data set, whose exact name escapes me at the moment. British and French cities are not the same as Symph maps', and the standard for their inclusion are unknown to me.