Thanks for your reply Vladimir,
I am using resources and grouping on them. The colour coding of the events is not based on the resource but rather the state in which the event is in. For example, if an activity is created in provisional state for Room A and another in tentative state for Room B. Both Room A and Room B are resources and the calendar is grouped by them but the activity (event) itself is coloured based on the state; provisional is red and tentative is blue (for example).
I want to be able to apply the colour to the event (for the entire k-event) based on the colours for different state of the activity (event). And hence, it starts of as provisional in red but than the state is changed to tentative and the colour changes accordingly to blue.
I hope this makes it clear what I am trying to achieve.
Looking forward to your response.