It wasn't grainy so much as stiff...
For example I had to warm/wet my smoothing tool to try and make the sides/top smooth. Even the smoothing tool left big marks in the icing before that and you can see the piping broke vs.coming to smooth points, but the decorating triangle when I tried to put a wave design on the sides? The lines became ragged vs. smooth, so had to start over and just try to make it all smooth.
The odd thing was everything in the bowl looked great, super smooth looking -- till I added the vanilla, so have no idea about that.
I do still have a bit of icing, but it's certainly warmed up as it's been out on the counter, but it still has the same sticky-stiffness.