Road network datasets must (for REF) and can (for OSM) be uploaded as a compressed ESRI shapfile. Click the Browse button, select the .zip file from your system and adjust its color using the Layer Color selector. Enter also the reference system of the dataset.
The OSM road network dataset can be also retrieved (using the Overpass API) by clicking the Retrieve OSM data button. This will retrieve OSM data for the current map view; alternatively, hold down the shift key to select a rectangle on the map view and then click the Selection Retrieve button.
When at least two datasets have been uploaded, click the Compare menu button. This will open a menu where you can specify the buffer width for the comparison, the datasets to be used as REF and OSM and (optionally) the mask for clipping the previous datasets - to be previously uploaded as a compressed shapefile. Then click the Start comparison button to run the algorithm and download some statistics on the similarity between the datasets in a PDF file.