You are not allowed to build new caves for burial on Chol Hamoed to be used for later use. However, to lengthen or shorten them is permitted.

You can make ponds for washing clothes on Chol Hamoed for the cases where washing is permitted.

If you are in a community where people do not know that there is a deceased you can only prepare the aron [box] if the corpse is in the same courtyard so all would know why you are doing it. R’ Yehuda says sawing new boards are prohibited.

Moed Katan 1:7

You are not allowed to do Nissuin on Chol Haamoed or Yibum as it brings simcha [happiness] and we do not mix the simcha of Chol Hamoed with another simcha. You could take back a previous wife.

A lady can do cosmetic procedures on Chol Hamoed. R’ Yehuda says she cannot put on lime as at first it makes her not pretty even though later it will make her look nicer.