Running 4.11 preview 7 and working with the Vive Pre. Calling the force feedback node (either dynamic or play effect) crashes the engine with no call stack and using play haptics effect node in BP does nothing (I assume it only works for Oculus Touch).
Got a call stack after downloading editor symbols for debugging
Access violation - code c0000005 (first/second chance not available)
UE4Editor_SteamController!FSteamController::UpdateVibration()
UE4Editor_Core!FWindowsApplication::SetForceFeedbackChannelValues() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\core\private\windows\windowsapplication.cpp:1835]
UE4Editor_Engine!APlayerController::ProcessForceFeedbackAndHaptics() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\playercontroller.cpp:3657]
UE4Editor_Engine!APlayerController::TickPlayerInput() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\playercontroller.cpp:3878]
UE4Editor_Engine!APlayerController::PlayerTick() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\playercontroller.cpp:1980]
UE4Editor_Engine!APlayerController::TickActor() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\playercontroller.cpp:3954]
UE4Editor_Engine!FActorTickFunction::ExecuteTick() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\actor.cpp:110]
UE4Editor_Engine!FTickFunctionTask::DoTask() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\ticktaskmanager.cpp:228]
UE4Editor_Engine!TGraphTask<FTickFunctionTask>::ExecuteTask() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\core\public\async\taskgraphinterfaces.h:886]
UE4Editor_Core!FNamedTaskThread::ProcessTasksNamedThread() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\core\private\async\taskgraph.cpp:779]
UE4Editor_Core!FNamedTaskThread::ProcessTasksUntilQuit() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\core\private\async\taskgraph.cpp:526]
UE4Editor_Core!FTaskGraphImplementation::WaitUntilTasksComplete() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\core\private\async\taskgraph.cpp:1534]
UE4Editor_Engine!FTickTaskSequencer::ReleaseTickGroup() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\ticktaskmanager.cpp:486]
UE4Editor_Engine!FTickTaskManager::RunTickGroup() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\ticktaskmanager.cpp:1373]
UE4Editor_Engine!UWorld::RunTickGroup() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\leveltick.cpp:702]
UE4Editor_Engine!UWorld::Tick() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\engine\private\leveltick.cpp:1187]
UE4Editor_UnrealEd!UEditorEngine::Tick() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\editor\unrealed\private\editorengine.cpp:1356]
UE4Editor_UnrealEd!UUnrealEdEngine::Tick() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\editor\unrealed\private\unrealedengine.cpp:370]
UE4Editor!FEngineLoop::Tick() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\launch\private\launchengineloop.cpp:2640]
UE4Editor!GuardedMain() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\launch\private\launch.cpp:142]
UE4Editor!GuardedMainWrapper() [d:\buildfarm\buildmachine_++ue4+release-4.11\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll