It happened to me too. Sometimes you're lucky and after reopening Layout you have a recent file, sometimes just nothing and you lose hours of work.
I solved it adding few lines to my autohotkey script, it generates a loop that autosaves every 2 minutes.
#Persistent
SetTimer, AutoSave, 120000
AutoSave;
IfWinActive, ahk_exe C;\Program Files\SketchUp\SketchUp 2016\LayOut\LayOut.exe
Send, {LCtrl Down}s{LControl Up}
return
where 120000 is the time in milliseconds.