@sdetweil Here is mine and it looks like it is read write enabled.

pi@pi:~/MagicMirror/css $ ls -laF
total 36
drwxr-xr-x 2 pi pi 4096 Sep 1 19:13 ./
drwxr-xr-x 17 pi pi 4096 Aug 25 15:48 …/
-rw-r–r-- 1 pi pi 12232 Sep 1 19:13 custom.css
-rw-r–r-- 1 pi pi 9032 Jul 14 01:01 custom.css.save
-rw-r–r-- 1 pi pi 2957 Jul 13 11:53 main.css
pi@pi:~/MagicMirror/css $ cd …
pi@pi:~/MagicMirror $ cd config
pi@pi:~/MagicMirror/config $ ls -laF
total 32
drwxr-xr-x 2 pi pi 4096 Sep 1 19:14 ./
drwxr-xr-x 17 pi pi 4096 Aug 25 15:48 …/
-rw-r–r-- 1 pi pi 8196 Sep 1 15:57 config.js
-rw-r–r-- 1 pi pi 3258 Jul 13 11:53 config.js.sample
-rw-r–r-- 1 pi pi 3305 Jun 15 16:17 configOriginal.js
-rw-r–r-- 1 pi pi 20 Jun 15 16:17 .gitignore
pi@pi:~/MagicMirror/config $