here's my script. I assume the problem is in the pressing, but idk what else to do about it
event.recipes.create.sequenced_assembly([
Item.of('minecraft:crafting_table')
], 'minecraft:oak_slab', [
event.recipes.createDeploying('create:incomplete_precision_mechanism', ['create:incomplete_precision_mechanism', 'harderworkbench:nail']),
event.recipes.createDeploying('create:incomplete_precision_mechanism', ['create:incomplete_precision_mechanism', 'harderworkbench:nail']),
event.recipes.createDeploying('create:incomplete_precision_mechanism', ['create:incomplete_precision_mechanism', 'minecraft:oak_slab']),
event.recipes.create.pressing
]).transitionalItem('create:incomplete_precision_mechanism')