had a previous save before adding mca because i got bored. when pressing the gift option it greys out all the other options like it should but no new window pops up. tried restarting game and reinstalling, same thing.

Does this also occur on a new world?

As I understand it, after clicking on the "gift" option all other options are "disabled", right?
If so, you should have the gift you will give the villager in your hand, and then right-click to give the gift. To exit just press ESC

Closing for lack of information and unable to reproduce.