Changing the default dekstop settings to a slideshow-background allows adding custom folders. But KDE 4.11.2 seems to not store those settings.

It forgets any setting, except that 'slideshow' was choosen.

Reproducible: Always

Actual Results:  
No settings saved.

Expected Results:  
Settings saved.

draget@fuckup ~ $ qdbus org.kde.kwin /KWin supportInformation
KWin Support Information:
The following information should be used when requesting support on e.g. http://forum.kde.org.
It provides information about the currently running instance, which options are used,
what OpenGL driver and which effects are running.
Please post the information provided underneath this introductory text to a paste bin service
like http://paste.kde.org instead of pasting into support threads.

==========================

Version
=======
KWin version: 4.11.2
KDE SC version (runtime): 4.11.2
KDE SC version (compile): 4.11.2
Qt Version: 4.8.4

Options
=======
focusPolicy: 0
nextFocusPrefersMouse: true
clickRaise: true
autoRaise: false
autoRaiseInterval: 0
delayFocusInterval: 0
shadeHover: false
shadeHoverInterval: 250
separateScreenFocus: false
placement: 4
focusPolicyIsReasonable: true
borderSnapZone: 10
windowSnapZone: 10
centerSnapZone: 0
snapOnlyWhenOverlapping: false
showDesktopIsMinimizeAll: false
rollOverDesktops: true
focusStealingPreventionLevel: 1
legacyFullscreenSupport: false
operationTitlebarDblClick: 
commandActiveTitlebar1: 0
commandActiveTitlebar2: 30
commandActiveTitlebar3: 2
commandInactiveTitlebar1: 4
commandInactiveTitlebar2: 30
commandInactiveTitlebar3: 2
commandWindow1: 7
commandWindow2: 8
commandWindow3: 8
commandWindowWheel: 31
commandAll1: 10
commandAll2: 3
commandAll3: 14
keyCmdAllModKey: 16777251
showGeometryTip: false
condensedTitle: false
electricBorderMaximize: true
electricBorderTiling: true
electricBorderCornerRatio: 0.25
borderlessMaximizedWindows: false
killPingTimeout: 5000
hideUtilityWindowsForInactive: true
inactiveTabsSkipTaskbar: false
autogroupSimilarWindows: false
autogroupInForeground: true
compositingMode: 1
useCompositing: true
compositingInitialized: true
hiddenPreviews: 1
unredirectFullscreen: false
glSmoothScale: 2
colorCorrected: false
xrenderSmoothScale: false
maxFpsInterval: 16666666
refreshRate: 0
vBlankTime: 6000000
glDirect: true
glStrictBinding: false
glStrictBindingFollowsDriver: true
glLegacy: false
glCoreProfile: true
glPreferBufferSwap: 0

Screen Edges
============
desktopSwitching: false
desktopSwitchingMovingClients: false
cursorPushBackDistance: 
timeThreshold: 150
reActivateThreshold: 350
actionTopLeft: 0
actionTop: 0
actionTopRight: 0
actionRight: 0
actionBottomRight: 0
actionBottom: 0
actionBottomLeft: 0
actionLeft: 0

Screens
=======
Multi-Head: no
Active screen follows mouse:  yes
Number of Screens: 2
Screen 0 Geometry: 0,0,1920x1200
Screen 1 Geometry: 1920,0,1920x1200

Decoration
==========
Current Plugin: kwin3_oxygen
Shadows: yes
Alpha: yes
Announces Alpha: yes
Tabbing: yes
Frame Overlap: no
Blur Behind: no

Compositing
===========
Qt Graphics System: raster
Compositing is active
Compositing Type: OpenGL
OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce 9600 GT/PCIe/SSE2
OpenGL version string: 3.3.0 NVIDIA 325.15
OpenGL shading language version string: 3.30 NVIDIA via Cg compiler
Driver: NVIDIA
Driver version: 325.15
GPU class: G80/G90
OpenGL version: 3.3
GLSL version: 3.30
X server version: 1.14.3
Linux kernel version: 3.11.4
Direct rendering: yes
Requires strict binding: no
GLSL shaders:  yes
Texture NPOT support:  yes
Virtual Machine:  no
OpenGL 2 Shaders are used
Painting blocks for vertical retrace:  yes

Loaded Effects:
---------------
kwin4_effect_zoom
kwin4_effect_dimscreen
kwin4_effect_slidingpopups
kwin4_effect_login
kwin4_effect_minimizeanimation
kwin4_effect_screenshot
kwin4_effect_slide
kwin4_effect_desktopgrid
kwin4_effect_translucency
kwin4_effect_maximize
kwin4_effect_fade
kwin4_effect_highlightwindow
kwin4_effect_taskbarthumbnail
kwin4_effect_dialogparent
kwin4_effect_presentwindows
kwin4_effect_blur
kwin4_effect_logout
kwin4_effect_dashboard
kwin4_effect_screenedge
kwin4_effect_startupfeedback
kwin4_effect_kscreen

Currently Active Effects:
-------------------------
kwin4_effect_dialogparent
kwin4_effect_blur

Effect Settings:
----------------
kwin4_effect_zoom:
zoomFactor: 1.2
mousePointer: 0
mouseTracking: 0
enableFocusTracking: false
followFocus: true
focusDelay: 350
moveFactor: 20
targetZoom: 1

kwin4_effect_dimscreen:

kwin4_effect_slidingpopups:
fadeInTime: 50
fadeOutTime: 50

kwin4_effect_login:

kwin4_effect_minimizeanimation:

kwin4_effect_screenshot:

kwin4_effect_slide:

kwin4_effect_desktopgrid:
zoomDuration: 60
border: 10
desktopNameAlignment: 0
layoutMode: 0
customLayoutRows: 2
usePresentWindows: true

kwin4_effect_translucency:

kwin4_effect_maximize:

kwin4_effect_fade:

kwin4_effect_highlightwindow:

kwin4_effect_taskbarthumbnail:

kwin4_effect_dialogparent:

kwin4_effect_presentwindows:
layoutMode: 0
showCaptions: true
showIcons: true
doNotCloseWindows: false
ignoreMinimized: false
accuracy: 20
fillGaps: true
fadeDuration: 30
showPanel: false
leftButtonWindow: 1
rightButtonWindow: 2
middleButtonWindow: 0
leftButtonDesktop: 2
middleButtonDesktop: 0
rightButtonDesktop: 0
dragToClose: false

kwin4_effect_blur:
blurRadius: 12
cacheTexture: true

kwin4_effect_logout:
useBlur: true

kwin4_effect_dashboard:
brightness: 0.5
saturation: 0.5
blur: false

kwin4_effect_screenedge:

kwin4_effect_startupfeedback:

kwin4_effect_kscreen: