1. select a set of points via load mask using e.g. the temporal coherence or the amplitude stability index. it does not make any sense to select points based on cumulative displacement

2. then check your results via histogram and scatter plots modules. you can check the histogram of the cumulative displacement to understand what is wrong. then you can plot it in SAR (or geographic) coordinates using scatter plots. in both modules you can apply additional sub-selections of points using the boolean conditions. Here you see examples of the use of histograms and scatter plots http://www.sarproz.com/publish/tutorials_partIII.pdf

3. if the cumulative displacement CumDisp.mat file is not there, it means it was not saved. Is the velocity there? If the velocity is there and the cumulative displacement not, it means you estimated a linear model, so, the cumulative displacement was not produced. To know to cumulative displacement, just multiply the velocity by the observation time. If the velocity is not there either, it means you did not save your results.