OK in the home directory I can switch to r/w but when I go to the system/apps folder it switches back to r/o and the mount r/w button does not do anything.
Had same issue. Fixed it by running Superuser Permissions, selecting Root Explorer and telling it to" forget" then reran Root Explorer and it will ask again if you wish to grant superuser status. Choose yes and it should let you mount r/w in system. Not sure why it stopped working first time for me, but this worked to restore. Good luck.
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