How can I change proportions of radar map?

Am trying to make large tall thin map for britain (for 1.6). Map_regions is currently 255 x 375 high. Would like to know if it possible to change proportion of hole in interface for radar map?

If I run without radar_maps it shows squashed version:
https://img93.imageshack.us/img93/1017/squished3by.jpg

If I try making one to the size of my map_regions (375 high) it crashes after faction selection during loading bar.

Can make a new radar_map1.tga to my proportions but only 156 high I get:
https://img93.imageshack.us/img93/6387/tall8zs.jpg

If anyone is wondering about the extreme continental drift that's brought Norway into map - I'm still having trouble with landmass v. map size CTD.