Terraform option was removed a long time ago. Since a terraformer was not needed anymore. Without a terraformer I don't know which player is terraforming the planet.
But, at the same time, I added a "Selected Planet Info". As soon as you choose the terraforming of a planet, with paused game, have a look at that section of the table and copy the content of "Days necessary to Terraform ==>" to "Days already passed to Terraform ==>" and will finish it when you unpause the game.