One of the first things you have to do in this pack is right click stone while shifting to get pebbles, so i try it with a open hand and ... Theres nothing, i have tried to redownload the pack make a new world too, and still cant get those pebbles...

Having this problem as well. Generally those pebbles are from Garden of Glass, which isn't in the pack... also in that same vein we have Ex Compressum, but don't have Ex Nihilo Sequentia, which is required to run that I believe... could be wrong. Anyway, I can't get pebbles either. I have worked around this by cheating in a storage drawer with a creative vending upgrade, a single pebble, and I'm good. That way I still have to at least click a few times to get pebbles. Unless I'm missing something though, there's no way to get pebbles. I know it works, I've seen videos of people playing and making it work, just not sure why mine isn't.

Seems to have been fixed at some point. I can get pebbles in 1.0.3

Why wasn't this closed ?
I think I'm having the same problem playing on a server... Dunno what to make of it