I think this is due to Packed Storage mod removing the recipe for vanilla chests. Placing non-vanilla planks in the crafting table in any but very specific crafting slots, creates a vanilla chest (e.g. placing planks in the middle row is the only way to create slabs. Any other row creates a chest as shown in picture). Placing a single plank in any crafting slot except the center slot, creates a vanilla chest etc..

Removing the Packed Storage mod fixed the problem.

Looks like something you need to report to them not us. if byg works entirely fine on its own, then this isnt our bug