I have a Moto E with a storage problem! Tt the time before installing i had 322 MB free storage and was about to get Dead Trigger 2 but I didn't have enough space so it stopped and now I have only 77 MB free? Did it keep half the app on my phone still?
If you look in Settings > Storage > Misc, there should be a temporary file called 'temp' or similar for downloading. 

Delete this and you should be fine.