Help with Blockbench Boots (SOLVED)

I have a problem

I'm making a full armour set with blockbench (Armor, helm, leggins and boots)

I start from a base biped model so I already find pre defined groups for head, left leg, right leg, body, right arm and left arm.

So no worries at all, my helmet, armour and leggings are wonderful

My problem is with boots I have no clue how to do boots !!!! There is no group for them and if I add one it's totally messed up so I believe adding a new group for boots is not a solution.

Probably I must work on leggings group and maybe add a sub-group for boots but even this case it does not work

Can anyone help ??