I don't know about such problems. Might be related to itch or your phone.
How exactly does it happen? Do you press download and it shows you an error message or can you download the file but can't use it afterwards?

I don't really know. Maybe your connection or that of itch is having problems? You could try downloading at https://gamejolt.com/games/Renryuu/152719 or https://mega.nz/#F!CpQXwBDS!wwZlWRrPWoGzZX5h0-MlRQ instead and see if that works.