I am using Mist with this script. It works and shows up on map with alt 0.
local vars =
{
type = "FARP",
country = 'USA',
category = "Fortifications",
x = -281290.125,
y = 646987.4375,
name = "FARP-01",
heading = 0.47123889803847,
}
mist.dynAddStatic(vars)
edit:
I forgot to change category.