when ever I take out the augmented sextant I begin lagging severly until a eventual crash

AS version, Forge version, resource utilization screenshot from task manager perf menu as well as in-game F3+A menu. Sounds like your hardware is just shitting itself, and you've given no information to look into this, as I'm not seeing this on my side.

@Rebelord01 Any update on the above request?

Might be related to a very specifically tailored world lacking certain notable features like biomes or structures leading to a long lookup-attempt...

Please reopen if there's more information to this.