Running Scope 5.1 software in 'native mode' works superb. I can execute XTC mode and I can load and play Scope based synths. But when (or after) I want to switch synth, I'm getting error message warning that 'A serious problem has occurred...'. Se attached image for more info.

Following synths crash usual after loading or unload, but never during performance playing in Scope environment:
BlueSynth
MiniScope MkII
Poison
Prisma
Here is a copy of Cubase crash log:
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Cubase6.exe Version 6.0.0 Build 229 - 20.2.2011 7:03
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Timestamp is 4cf95e35 (Fri Dec 03 22:16:37 2010)
C:\Program Files (x86)\Steinberg\Cubase 6\Cubase6.exe
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Exception code: C0000005 ACCESS_VIOLATION
Fault address: 7784E3BE 01:0001E3BE C:\Windows\SysWOW64\ntdll.dll
Registers:
EAX=056abf40 ECX=18580000 EDX=185e4a98 EBX=185e4a98 ESI=7fa46981 EDI= 185e4a90
EBP=0018ef7c EIP=7784e3be ESP=0018ef48 CS= 00000023 SS= 0000002b Flags=00210206
DS= 0000002b ES= 0000002b FS= 00000053 GS= 0000002b
Float Save:
Control Word= 0000027f Status Word= 00000120 Tag Word=0000ffff
Error Offset= 09737bc7 Error Selector=05d80023
Data Offset= 0018e4dc Data Selector= 0000002b
Cr0NpxState= 0a3b1858
Bytes at CS:EIP:
8b 46 04 89 45 f4 c6 47 07 80 c6 47 06 00 8b 5e
08 8b 4e 0c 89 5d e0 83 c3 01 89 4d e4 83 d1 01
Call stack:
Address Frame
7784E3BE 0018EF7C RtlInitUnicodeString+196
7784E023 0018EF94 RtlFreeHeap+7E
759314D1 0018EFA8 HeapFree+14
0CEE87D7 0018EFE8 0001:000177D7 C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CEDE266 0018F010 0001:0000D266 C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CED938C 0018F02C 0001:0000838C C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CED932F 0018F038 0001:0000832F C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CEE2F48 0018F058 0001:00011F48 C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CED361F 0018F074 0001:0000261F C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CED35BF 0018F080 0001:000025BF C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CED313C 0018F0A4 0001:0000213C C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CEFB329 0018F0B0 0001:0002A329 C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CEFBE8F 0018F0BC 0001:0002AE8F C:\Program Files (x86)\Steinberg\Cubase 6\Components\VSTPlugManager.dll
0CF0A571 0018F0EC GetPluginFactory+D0D1
0CF0A72B 0018F0F8 GetPluginFactory+D28B
0108F0CF 0018F140 0001:00C8E0CF C:\Program Files (x86)\Steinberg\Cubase 6\Cubase6.exe
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Before I contact Steinberg, I want to see if you people can recommend some solution.
Thanks in advance.