* continue to pick "new" colours for coloured layers even when all colours have been used at least once, rather than sticking on the last one * some messing about with application palette settings * when replacing an audio file, retain the previous playback settings for any layers that depended on the old file * re-check plugin program setting when a parameter changes -- so a plugin can decide to reset the program if the parameters no longer match those for the current program * fix failure to update check-boxes for toggled plugin parameters when their parameters are changed by program changes