Shoutbox

This may help, Main Messenger Window > Plus! > Preferences > Logging > Archiveing and you'll see near the left bottom corner a Automatic save delay that you can change the time of...you could make it lower if your PC is prone to crashing....
Apart from that there's no way to make Plus! log when your PC crashes because when a PC crashes the Plus! process usually stops or locks up along with virtually every other process...