After getting the update installed, I can't confirm the behaviour you're getting, everything seems to work as normal. Most likely it's due to incorrect file attributes/ownership set for the MyDocs folder (and subfiles) as having owner/group set to root/root would prohibit non-elevated applications (camera for instance) to store data there. In my case the owner/group of MyDocs and subfiles/-folders is set to user/root, and I'm fairly sure that's how it's suppose to be. Seeing as it reverts the ownership when you try to change it, maybe it's caused by some monitoring process and/or improper settings for mounting it. For me, mount | grep MyDocs gives Code: /dev/mmcblk0p1 on /home/user/MyDocs type vfat (rw,noatime,nodiratime,noauto,nodev,exec,nosuid,utf8,uid=29999,shortname=mixed,dmask=000,fmask=0000,rodir) and ls -lAd /home/user/MyDocs Code: drwxrwxrwx 30 user root 65536 Dec 27 08:49 /home/user/MyDocs Maybe you run those and compare.
/dev/mmcblk0p1 on /home/user/MyDocs type vfat (rw,noatime,nodiratime,noauto,nodev,exec,nosuid,utf8,uid=29999,shortname=mixed,dmask=000,fmask=0000,rodir)
drwxrwxrwx 30 user root 65536 Dec 27 08:49 /home/user/MyDocs