The selector and generation with a backslash (\\\\)

When setblock, summon generated by a backslash (\\\\) of the time, a few will generate a backslash The selector does not support the absolute coordinates (+?) , and m (player game mode, such as creation, etc.), anti can not be used (m=! 1 can still detect the creation mode)

My first question is when using the command "one command", I need to put word with Click event on a sign like text message

My second question is that I can't use the relative coordinates of the selector, such as @e[x=~+10, y=~-20, z=~5], I know that this can be solved by execute, but still want to solve the problem.

My third question comes from cheating, in the 1.8 version of the time, @a[m=! 1] can choose players in addition to the creation mode, and in the preview version of my now can not use

Hope who can solve it