The Road Vehicle Lighting Regulations 1989 as you can imagine cover more than just MINI, the full document can be found here.
This section of the site takes the general regulations and removes all parts that are not relevant to post 2000 MINI.
However, you should satisfy yourself that the interpretation given is adequate for your needs. No liability can be accepted for the interpretation given or its application.
As there is lots to it I've broken it down in to the following sections, but please note that what applies in one area can have an impact on another e.g. a light at the front could be visible at the side, and rules apply ...