Temporal sorting is done using a SPM (SPM2 or SPM5) design matrix. You can create SPM design matrix from an ASCII file containing regressor time courses using "Utilities" drop down box. Under "Utilities" drop down box select 'Ascii_to_spm.mat'. The time course matrix must be in dimensions m by n where m is the sum of the number of scans over sessions and n is the number of total regressors. Type help icatb_formDesignMat at the MATLAB command prompt for an example. See icatb/icatb_templates folder for example regressor data files.