Hi Maris,
Buying Propensity in 1511 needs data from CRM. So if you don't have a connected CRM system the corresponding tables will empty and Buying Propensity cannot be used.
We changed that in 1602. Here the the Buying Propensity uses Contact and Interactions as basis for calculating BP. All necessary date to calculate BP can be loaded via Interactions (sales data, products etc.)
BR,
Janusz