Open the Sonar project file you want to convert. Select "File," and then click the "Export" option. Choose a destination folder where the project copy will be saved. Click the drop-down menu next to "Format." Select the ".OMF" option. Wait for the program to finish the export process.
Click "File," and then select "Export" again. Navigate the browser to find the same destination folder you previously chose. Click the format drop-down menu, and choose "MIDI Format 1." Click the "OK" button, and Sonar begins exporting all MIDI files inside your project.
Open the Cakewalk Cubase program. Select "File," and then click the "Import" option. Use the browser window to find the folder where you saved the .OMF and MIDI files. Select all of the files within the folder, and then click "Import." The import process may take a few minutes to complete.
Click "File," and then select "Save Project As." Choose a destination folder for the new Cubase project. Type a name for your project, and then click "OK." All files in the project are saved as a .cpr Cubase file.