You can make a fence for a maake [so people shouldn’t fall down] on a roof on Chol Hamoed, however only in an unskilled way.

You can plaster cracks with your hands or feet, however using a roller or trowel which is the normal way is prohibited.

A hinge, pipe, beam, lock, or key, that broke can be fixed on Chol Hamoed as long as you did not leave it from before Yom Tov to be fixed on Chol Hamoed.

You can pickle food on Chol Hamoed to eaten later on Yom Tov.

Moed Katan 2:1

When one of 7 close relatives die [father, mother, son, daughter, brother, sister or spouse] a person must sit seven days for what is called shiva. During these days you are prohibited to do work.

When you squeeze olives, first you leave them in a vat to get soft. Then they are turned over once and following that you have a short time in which to have them pressed otherwise they will spoil.

R’ Yehuda says if you turned over your olives and you became an avel before Yom Tov and did not finish pressing the olives and now it became Chol Hamoed, you can put a beam on the olives once to make them drip. This is also true if some other uncontrollable circumstances occur to stop the pressing from happening before Yom Tov such as the workers stopped working right before Yom Tov. R’ Yosee says you can complete the process and close the barrels.