To change your default layer:
Make sure that OneCNC is not runing.
1) open windows explorer and get to the file that onecnc settings are in,Something like (onecnc-xp/mill expert/setting/users)
2) in the file you just got to above there will be a folder named default or (a user name IE: some name you set up) open this folder up.
3)Open the file name (setting.ini) This will open into it's own window, look for this line in the file (defaultlayer= ) it's about 8 to 10 lines down, then edit the line to say (defaultlayer=default) or anything you want to be your default layer name IE: 0 or one or first or Ken's stuff.
4) at the top of the file window in the title bar select (file/save) then close the file and all the other windows you have open and your done.
you can do this for any user accounts you have set up.