Sethmaster and lucid, regarding the seams issue - this might solve it, and might not, but I was having an issue with sprites lagging and jumping around, and so I made the spriter object set it's x and y to int(object.x) and int(object.y) (where object in this case would be your placeholder sprite) as opposed just object.x and object.y. I guess the issue was that it was trying to align sprites based on coordinates that weren't necessarily whole numbers, so it would round up or down. seems to work well for me, hopefully that helps for you guys. I haven't exported to nwjs, and I'm only guessing on what I think you're referring to with that issue, so maybe this is completely irrelevant.