That's not good especially if you used any kind of blur or dodge tool which are not allowed in the Pixeljoint gallery.

Its cool to use as many colors as you want but its not cool if your app adds them for you losing control 'on the pixel level' which is the standard all use for pixelart here.

I too use PS to pixel and for all pixelart, but especially animations its best to 'save for web' so that no CGd artifacts are added which is what it looks like has happened here.

I use Photoshop CS6, and the exports are similare to the psds. I probably do not have the best export settings though, but it's also true that I do not really pay attention to how many colors I can use for my scenes. In this case, it's just me trying (badly) to add some texture to the buildings I'm afraid. ^^' 

The file shows 244 colors which is really, really high. This may be an output issue when making the animation. What is your animation app? Are you sure your seetings are all good and not adding pixels, colors and artifacts?

I agree. I'll try to go for a simpler/cleaner background next time. Thanks! 

Such a lovely scene.
I don't really like all that noise and messy pixelling in some of the buildings.
It hurts the piece :/