Help!!!Something wrong with the 64x or higher texture in 0.9.0

Thanks for your reading.
I am fond of MCPE textures and I made the textures by myself.
There is something wrong with the flower texture.
When the texture is 64x or higer,the background of flowers(not double flowers) and mushrooms is opaque !
I once throught its my texture's problem ,so I did nothing but turn it into 32x,the problem solved.And other people found the same problem too!
Well, I hope you can solve it or we will have no more 64x or higher texture to use! What a pity!