[embryo]

Using version 634, I can't make Koreader start (with or without defaults.persistent.lua)
I get this crash.log:

./luajit: frontend/ui/device.lua:79: bad argument #1 to 'sub' (string expected, got nil)
stack traceback:
	[C]: in function 'sub'
	frontend/ui/device.lua:79: in function 'getModel'
	frontend/ui/device/screen.lua:145: in function 'getDPI'
	frontend/ui/gesturedetector.lua:53: in main chunk
	[C]: in function 'require'
	frontend/ui/input.lua:2: in main chunk
	[C]: in function 'require'
	frontend/ui/uimanager.lua:3: in main chunk
	[C]: in function 'require'
	frontend/ui/widget/button.lua:9: in main chunk
	[C]: in function 'require'
	...
	frontend/ui/widget/buttondialog.lua:1: in main chunk
	[C]: in function 'require'
	frontend/apps/filemanager/filemanagerhistory.lua:3: in main chunk
	[C]: in function 'require'
	frontend/apps/filemanager/filemanager.lua:1: in main chunk
	[C]: in function 'require'
	./reader.lua:22: in main chunk
	[C]: in function 'dofile'
	./koreader-base:22: in main chunk
	[C]: at 0x0000bd85

Any hint?

Update: The problem was crated because I had copied an extra Koreader Folder to the root.
After deleting this folder all versions (including 634) are working OK.

Sorry for the false alarm...