UE4 crashes when using simplygon

Hello, i have this problem, engine crashes after i am trying to use simplygon ( whether to generate LOD for skeletal mesh or to merge actors)
The simplygon on 4.15 worked well but after i installed 4.16 version and then installed simplygon on it, This issue (crash on generating) begin to occur in both versions.
I deletetd simplygon ( SDK, Grid, ue4 plugin - all components) and then reinstalled it on 4.16 - doesnt work ( crashes are still present). I thought that maybe this is the issue with engine, so i deleted 4.16 and simplygon, and then reinstall it for 4.15 - crashes remain. Deleted all versions of engine, and simplygon - reinstalled - crashes are still present

Access violation - code c0000005 (first/second chance not available)

UE4Editor_SimplygonMeshReduction!FSimplygonMeshReduction::ProxyLOD() [d:\build++ue4+release-4.15+compile\sync\engine\source\developer\simplygonmeshreduction\private\simplygonmeshreduction.cpp:947]
UE4Editor_MeshUtilities!FMeshUtilities::CreateProxyMesh() [d:\build++ue4+release-4.15+compile\sync\engine\source\developer\meshutilities\private\meshutilities.cpp:6224]
UE4Editor_MergeActors!FMeshProxyTool::RunMerge() [d:\build++ue4+release-4.15+compile\sync\engine\source\editor\mergeactors\private\meshproxytool\meshproxytool.cpp:127]
UE4Editor_MergeActors!SMergeActorsToolbar::OnMergeActorsClicked() [d:\build++ue4+release-4.15+compile\sync\engine\source\editor\mergeactors\private\smergeactorstoolbar.cpp:146]
UE4Editor_MergeActors!TMemberFunctionCaller::operator()<>() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegateinstanceinterface.h:165]
UE4Editor_MergeActors!TTupleImpl >::ApplyAfter >() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\tuple.h:134]
UE4Editor_MergeActors!TBaseSPMethodDelegateInstance<0,SMergeActorsToolbar,0,FReply __cdecl(void)>::Execute() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:327]
UE4Editor_Slate!TBaseDelegate::Execute() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:537]
UE4Editor_Slate!SButton::OnMouseButtonUp() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\widgets\input\sbutton.cpp:278]
UE4Editor_Slate!::operator()() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5075]
UE4Editor_Slate!FEventRouter::Route >() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:238]
UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5064]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5531]
UE4Editor_Slate!FSlateApplication::OnMouseUp() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5508]
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1698]
UE4Editor_Core!FWindowsApplication::DeferMessage() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:2120]
UE4Editor_Core!FWindowsApplication::ProcessMessage() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:867]
UE4Editor_Core!FWindowsApplication::AppWndProc() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:714]
user32
user32
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:980]
UE4Editor!FEngineLoop::Tick() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2977]
UE4Editor!GuardedMain() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\launch.cpp:166]
UE4Editor!GuardedMainWrapper() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:134]
UE4Editor!WinMain() [d:\build++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:210]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll

4.16 also crashes when i’m trying to use simplygon features. it’s all happens even on standard projects

Same bug for me : fresh install of simplygon. even on the EPIC mannequin.

Call stack :
UE4Editor-SimplygonMeshReduction.dll!FSimplygonMeshReduction::CreateSkeletalHierarchy() [d:\build++ue4+release-4.15+compile\sync\engine\source\developer\simplygonmeshreduction\private\simplygonmeshreduction.cpp:1529]
UE4Editor-SimplygonMeshReduction.dll!FSimplygonMeshReduction::ReduceLODModel() [d:\build++ue4+release-4.15+compile\sync\engine\source\developer\simplygonmeshreduction\private\simplygonmeshreduction.cpp:247]
UE4Editor-SimplygonMeshReduction.dll!FSimplygonMeshReduction::Reduce() [d:\build++ue4+release-4.15+compile\sync\engine\source\developer\simplygonmeshreduction\private\simplygonmeshreduction.cpp:355]

Same issue for me on 4.16.1

Will there be any comment from developers? This bug is still didn’t fixed neither in 4.15 nor in 4.16