What type of cultural acclimitazation programme can be designed for a
UK expatriate staff moving to Kenya?

Research Malaria drugs
- get the latest - the bugs develop immunity

- a pal of mine darn near died of Malaria picked up in Kenya

Talk to the Foreign Office or UK aid organisations, churches with
missionaries there.
You want to set up a programme: for people doing what, living in what stratum?

Business management staff and wives probably need instruction about
dealing with household servants.  That can be important; security and
also because if they make mistakes at the start, the grapevine won't
work in their favour.
Persons working closer with the populace need more awareness of the
social environment in which they will be active and in a different way
about security.  Health and sanitary conditions and precautions, also
knowing what to do in an emergency should be covered, that they should
let British authorities know that they are there and where, and not
avoid contact with "the community," even if, say, your people might
prefer to eshew such contacts.
No, I haven't been to Kenya, but elsewhere.   These are just a few suggestions.