How do you mean everyone in the palace does not gain experience?
The experience of governor starts to amass from the appointment on the post. The governors gain points for their governing time, 1 experience point is earned for 6 min. The experience of governor is only earned while the Great person is on the post. If the player did not appoint him to the position or the Great person entered into battles in this time, no experience is acquired.
Please read for further info:
http://www90.imperiaonline.org/imperia/game_v6/game/help/?section=great_persons&lang=en&speed=2#great_persons_52There isn't a problem into your account.
The option for merging buildings isn't available yet. There will be detailed explanation when the option is activated.