I know how to use Inkscape, I just don't like it.
You can't create custom polygons point-by-point, vertex snapping doesn't work, and the whole thing is sloppy and imprecise.
I don't want to make my maps with it.
I typically draw polygons one point at a time, tracing an image very accurately.
Then, I can perfectly align the boundaries of each polygon so there's no overlap.
I've been making maps as a job for years, and I like being effective and efficient.
There is a way to change units, but pixels aren't an option.
I even made my own custom datum, but the unit is saved as "<Unknown Unit>", and the uploader looks for "Pixel".
Oh well.
EDIT::
I got it to work.
I can open my ArcGIS SVG in Inkscape, apply the Id's, and change the document unit to PX.
Then, I can upload to Warlight without issue.
Here's the test map, in case you guys want to see how it came out.
Looks nice and clean. :D
https://www.warlight.net/SinglePlayer?PreviewMap=56842
Edited 5/23/2016 22:02:17