Loading Package ... HillTree_02

I was trying to following the steps of Procedural Foliage Tool Quick Start, but as soon as I select HillTree_02 in Foliage type it shows progress bar with Loading Package … HillTree_02 at some percentage like 85% or 95% and stuck there for long time, I tried multiple times each time it becomes stuck at different %age I had to end task the UE4 each time since it do not allow to do anything else.

Is this issue with UE4 or my graphics card, I have 1gb NVidia GTX 645? my processor is i7 and RAM is 16GB.

Let me know.

Anyone have an answer for this?