Is it possible to run certain threads when Debug Engine stopped in "break mode"?

I need to continue execution of some threads when debugger stopped on breakpoint.
Something like calling

ContinueDebugEvent(***, ***, DBG_REPLY_LATER)

in the my Concord component. I've tried to call ContinueDebugEvent with DBG_REPLY_LATER flag in the IDkmRuntimeBreakpointNotification.OnRuntimeBreakpoint callback, but of course Concord didn't like that.

In documentation I've found this enum:

DkmStoppingEventProcessingNextAction
    // This status value is used when one or more threads are not at a safe point, so the
    // target process must be slipped. The target process is expected to hit one or more
    // stopping events (breakpoint or exception) in order to indicate that a safe point
    // has been reached.
	SlipTarget = 1,

which is used in the DkmProcess.StoppingEventProcessingContinue function. Looks like exactly what I need, but there's no any other information how to use it.
Can anyone help me with this problem?

Context:
I'm writing my own debugger with C++ and custom scripting language mixed-mode debugging support. Debugger contains two Debug Engines: my own AD7 debug engine (controls scripting language breakpoints, variables, callstack and etc), and standart Visual Studio C++ debug engine (DkmEngineId.NativeEng). They are packed and work together:

DebugLaunchSettings settings;
settings.LaunchDebugEngineGuid = DkmEngineId.NativeEng;
settings.AdditionalDebugEngines.Add(_MyScriptingDebugEngineGuid_);

To interact with scripting language VM (which is hosted inside debugged C++ program) - to set breakpoints / get callstack frames / and other stuff - I use RPC calls from my debugger to the VM service thread.
Everything is working fine. Until I stopped in the native C++ breakpoint. When this happens, all debugged process threads are frozen and I can't communicate with VM...
So, is it possible to continue executing some threads when debugger has stopped at breakpoint?

Start by reviewing DkmProcess.StoppingEventProcessingContinue and DkmStoppingEventProcessingNextAction, then trace the IDkmRuntimeBreakpointNotification.OnRuntimeBreakpoint callback in the two-engine setup described. Done means establishing whether selected threads can run during a native breakpoint and identifying the supported API sequence or documenting that this is not supported.