Install the APK. Do not open it yet. First, copy your old .novabackup file into Internal Storage/NovaLauncher/ . Now open Nova. It will ask if you want to restore. Say yes. Reboot your phone for gesture stability.
This version includes extensive support for adaptive icon shapes (Round, Squircle, Teardrop, etc.) even for legacy apps. Desktop Search Bar Customization: nova launcher 6.2.19
Are you still running Nova 6.2.19? Share your setup and backup files in the comments below. Install the APK