Hello NH,
Just to clarify, the resource chart can display Operations, Activities etc. for each order. In order to have separate colors for individual SKU's, in the Planning Board Profile you need to look at the Decision Table for graphical objects for the Resource Chart.
Now here you have to define the sequence in which the system reads each operation through the decision group, decision etc. and what graphical object is assigned.
Now you need to create a Decision Group-Decision combination for table Product, field selection AT104 or AT105 ( free attributes from Location-Product) and if this condition is true, you assign a graphical object which has your desired color.
If you have already done this, please make sure that you changed the colors for Process time as well under Graphical elements for your graphical objects.
Regards
AK