Fix for locking the UI when importing large numbers of previously unseen jams, name resolution was butting against the import process. Non-destructive, but alarming.
Finally actually persist the Jam Visualisation settings across sessions. Add a basic indicator for riff-gaps instead of just blank space.
NOTE: for Windows users, you may have to update your Visual Studio runtimes if LORE/BEAM immediately closes when you try launching them. The latest installer is included in the Windows package below, or download and run it direct from Microsoft https://aka.ms/vs/17/release/vc_redist.x64.exe