I added the mod to a semi-large modpack and upon crafting the items from the mod everything is fine but as soon as I add a few items to the tablet(both the block and the handheld) my game gets super choppy and eventually crashes, upon reload of the world I am back at the point before I crafted any item from the mod

Is that tablet an Alchemy Table or an Alchemy Pad?
Hmm, maybe there's a big looping process somewhere.

Could you also tell me the version of MCPitanLibarch and ItemAlchemy?

Probably, the version of MCPitanLibarch is old, so it will be closed. If there is anything, please reopen the issue again.