If the option "Distribution" of the stochastic parameter is set to "Lambda Distribution", the fitting of its probability distribution density from data of MS Excel table will be available. Select on the field "Distribution Fitting" and click the right button to show the fitting dialog for the lambda distribution.
In the left window, all stochastic parameters of the experiment are listed. First, select all distribution items beeing fitted by data. Than, click the button "Import" to open an Excel file. The first data block of the first Excel table will be imported. The data columns will be assigned to the selected distribution items in order. So the selected distributions will be fiited by the column data.