To use LoadVersion in C++ do the following:
Import the ArcGISVerion.dll
#import "libid:6FCCEDE0-179D-4D12-B586-58C88D26CA78" no_namespace raw_interfaces_only no_implementation rename("esriProductCode", "esriVersionProductCode")
You may have to rename the esriProductCode because it is also in esriSystem. Then add the following line before any ArcObjects code.
IArcGISVersionPtr ipVer(__uuidof(VersionManager));
VARIANT_BOOL succeeded;
if (FAILED(ipVer->LoadVersion(esriArcGISEngine, L"9.4", &succeeded)))
return 0;
You are right, the C++ sdks are currently are not available for Beta 1.