Thank you for reporting these errors, they have now been resolved and should work normally, you can now re-download the new asset pack
These are working fantastically now! I unfortunately spoke too soon regarding the models facing being backwards only on those trees. It does appear the bushes and many of the grass models are backwards as well.
Sorry to be a pain! I wish I knew how to make the adjustment on my own, but I just don't. On a side note, are you interested in possible commission work? I have a need for a tiled grass asset in this style.
I have solved the problems you have listed, about the grass you will simply have to rotate it to show it, this is caused by the normals being that unity only calculates the front normals and the grass is only a sheet and not a complete solid. Regarding the commission, of course, I am available, contact me on one of my social media and we can discuss it privately