problem solved. I had to fix DLLImport from SentinelSetupW.dll:
public sealed class SentinelKeySetupNativeAPI
{
[DllImport("SentinelSetupW.dll",
CharSet = CharSet.Ansi,
EntryPoint = "SFNTGetLibVersion")]
public static extern uint SFNTGetLibVersion(
/* OUT*/ out uint libVersion);
[DllImport("SentinelSetupW.dll",
CharSet = CharSet.Ansi,
EntryPoint = "SFNTLocateKey")]
public static extern uint SFNTLocateKey(
/* IN */ ref System.UIntPtr licHandle, //Device handle out param, for SP_FIND_FIRST and INOUT for SP_FIND_NEXT
/* IN */ ulong flags, //SP_FIND_FIRST or SP_FIND_NEXT
/* IN */ ulong devID, //Developer ID
/* OUT */ ref SPP_DEVICE_INFO si); //Device information, for the token located.
[DllImport("SentinelSetupW.dll",
CharSet = CharSet.Ansi,
EntryPoint = "SFNTProgramKeys")]
public static extern uint SFNTProgramKeys(
/* IN */ System.UIntPtr licHandle, //Device handle out param, for SP_FIND_FIRST and INOUT for SP_FIND_NEXT
/* IN */ byte[] licenseBuffer, //licenseBuffer
/* IN */ ulong length,
/* OUT */ string logFileName);
}