Let's clear up some misconceptions first.
The border width on Warlight *does not* depend on the width you set in the SVG file - it will be overwritten. That's why you didn't see any change.
However, the SVG file border width should be adjusted to be the same as the WL border width - so you are seeing the same thing on the site and in Inkscape / other editor. Currently I'm not sure what the width is (it was supposed to be 1.4 px wide, but Moros's test seems to indicate it's actually 1 px), but you should determine it (just look closely at some detailed part of border on Warlight and adjust widths in Inkscape until images match).
Also, I think you know this, but for posterity: if the territories you draw have overlapping border, they will not magically un-overlap when uploaded to Warlight - you'll have to do it by hand.
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Right. Now your border widths are perfect (make sure they are the same on all territories!). Do borders between bonuses overlap? If no, great. If yes, do this:
Consider two adjacent territories, belonging to different bonuses, with (maybe partially) overlapping borders. What you need to do is this:
* copy first one, paste it in the same place (Ctrl-Alt-V), convert it's stroke to path (Path -> Stroke to Path)
* do the same to the second one
* select first object and outline of the second, use Path -> Difference
* select second object and outline of the first, do the same
* the borders should now no longer overlap, just touch
This is boring work, since you need to do this for every pair, but it requires little to no though - just "automatic" clicking and using keyboard shortcuts. Maybe it could be actually automated - I'll try to look into creating an Inkscape extension for this next week, when I'll have more time. (No promises.)
[I copied the above from my response to earlier thread:
]http://warlight.net/Forum/Thread.aspx?ThreadID=2925]