[Galaxy Tab 10.1 Android Development] FCKöln:
Here is what i tested so far. The dock itself seems to be detected by this 5.1 ROM. When attaching i can see some output using logcat

06-22 14:18:50.385: D/MPLSensor(428): cb_onMotion:1
06-22 14:18:55.623: I/DockObserver(428): Dock state changed from 0 to 1
06-22 14:18:55.672: I/ActivityManager(428): Config changes=200 {1.0 ?mcc?mnc de_DE ?layoutDir sw800dp w1280dp h727dp 160dpi xlrg land desk finger -keyb/v/h -nav/h s.18}
06-22 14:18:55.788: I/Sandman(428): Activating dream while docked.
06-22 14:18:55.793: I/PowerManagerService(428): Nap time (uid 1000)...
06-22 14:18:55.797: W/DreamManagerService(428): Dream ComponentInfo{com.google.android.deskclock/com.android.deskclock.Screensaver} does not exist
06-22 14:18:55.797: W/DreamManagerService(428): Falling back to default dream ComponentInfo{com.google.android.deskclock/com.android.deskclock.Screensaver}
06-22 14:18:55.797: I/DreamManagerService(428): Entering dreamland.
06-22 14:18:55.797: I/PowerManagerService(428): Dreaming...
06-22 14:18:55.804: I/DreamController(428): Starting dream: name=ComponentInfo{com.google.android.deskclock/com.android.deskclock.Screensaver}, isTest=false, canDoze=false, userId=0
06-22 14:18:55.805: W/ActivityManager(428): Unable to start service Intent { act=android.service.dreams.DreamService flg=0x800000 cmp=com.google.android.deskclock/com.android.deskclock.Screensaver } U=0: not found
06-22 14:18:55.805: E/DreamController(428): Unable to bind dream service: Intent { act=android.service.dreams.DreamService flg=0x800000 cmp=com.google.android.deskclock/com.android.deskclock.Screensaver }
06-22 14:18:55.805: I/DreamController(428): Stopping dream: name=ComponentInfo{com.google.android.deskclock/com.android.deskclock.Screensaver}, isTest=false, canDoze=false, userId=0
06-22 14:18:55.817: W/Launcher(1069): setApplicationContext called twice! old=com.android.launcher3.LauncherApplication@2bb1c99d new=com.android.launcher3.LauncherApplication@2bb1c99d
06-22 14:18:55.848: W/ResourceType(1069): Attempt to retrieve bag 0x7f0d0008 which is invalid or in a cycle.
06-22 14:18:55.884: D/Launcher(1069): 11683562 - bindAddScreens()
06-22 14:18:55.884: D/Launcher(1069): 11683562 - orderedScreenIds:
06-22 14:18:55.884: D/Launcher.Workspace(1069): 11683562 - addExtraEmptyScreen()
06-22 14:18:55.884: D/Launcher.Workspace(1069): 11683562 - insertNewWorkspaceScreen(): -201 at index: 0
06-22 14:18:55.923: W/ResourcesManager(1069): Asset path '/system/framework/com.google.android.media.effects.jar' does not exist or contains no resources.
06-22 14:18:55.990: V/WindowManager(428): Adding window Window{23f567a8 u0 com.android.launcher3/com.android.launcher3.Launcher} at 4 of 9 (after Window{2297e00d u0 com.android.systemui/com.android.systemui.recents.RecentsActivity})
06-22 14:18:56.085: I/WindowManager(428): Screen frozen for +382ms due to Window{23f567a8 u0 com.android.launcher3/com.android.launcher3.Launcher}
06-22 14:18:56.152: I/PowerManagerService(428): Waking up from dream (uid 1000)...
06-22 14:18:56.158: E/WifiStateMachine(428): WifiStateMachine CMD_START_SCAN source -2 txSuccessRate=27,20 rxSuccessRate=19,45 targetRoamBSSID=DELETED RSSI=-77
06-22 14:18:56.158: E/WifiStateMachine(428): WifiStateMachine starting scan for "DELETED"WPA_PSK with 5220
06-22 14:18:58.274: I/art(428): Explicit concurrent mark sweep GC freed 24150(1318KB) AllocSpace objects, 6(96KB) LOS objects, 22% free, 13MB/17MB, paused 1.221ms total 119.997ms

USB debugging works when the tablet is attached to the keyboard dock and the usb cable from my pc is attached to the dock. The keyboard does not work at all. I have installed the "KeyTest.apk" and there is not a single output when pressing keys on the dock.

I then installed cm-11-20141008-1556-p4wifi.zip as a secondary ROM using the new multirom feature and this ROM was able to detect the keyboard. I was able to navigate through apps, start the browser/mail. Some buttons, like microphone, brightness, play/pause fwd/rwd were not recognized but i guess this is only because of some missing mappings in the key layouts file. I did not install google apps, this might also be the reason why some buttons did not work. Anyway, installing KeyTest.apk showed that all keys are recognized.

btw, are we talking about the ECR-K14D dock? because this is the one i am using...