Q:

Values cannot be changed in CompizConfig System Manager (CCSM) when using 

I'm trying to change the value "Left Maximize" to <Control><Super>Left, succeeding in grabbing the key combination.
But after a second, the value returns to the previous key combination. See screencap below.
What's preventing me from changing the key combination and how can I bypass it? Thanks.
UPDATE: It seems that only shortcuts with the <super> key are being reverted back to default. (Changed the question's title)
* Note that this is a pre-installed version for Dell.
.

A:

Found a workaround but still don't understand why the super key is locked from usage.
Steps for the workaround:
1. Change the key in CCSM to something without super (Should work).
2. Find the new key in dconf dump. dconf dump / | less + search for the new key combination. Found something of the following:
[org/compiz/profiles/unity/plugins/grid]
put-maximize-key='<Control><Alt>Up'
put-restore-key='<Control><Alt>Down'
left-maximize='<Alt>Left'
3. Write the new value. Example:
dconf write /org/compiz/profiles/unity/plugins/grid/left-maximize "'<Super><Control>Left'" (see the left-maximize in the command)
4. Check that it was written correctly:
$ dconf read /org/compiz/profiles/unity/plugins/grid/left-maximize
'<Super><Control>Left'

