I'm playing with this mod on the Hermitpack Modpack and I found a bug.

If you crouch while using the tome of Alkahestry, it gives you the item, but the book doesn't use any Redstone.
I now have 2500 Wither stars for free.

What version of Reliquary have you got? And does that not happen if you just duplicate the items without using shift?

I have version 1.3.3.581.

I tried it without using shift and I could replicate the nether stars without using shift.
So far I managed to get over 15,000 nether stars without the tome losing any power or needing recharged

So that is the bug that was fixed in version 585, you just need an updated version of Reliquary then.

Excellent. Sorry for the Bug report. As I said, I'm using it in the Hermitpack and their version must be out of date