Xamarin SQLite Unit Testing 64-Bit Windows

I'm developing a Xamarin application that uses a SQLite database, we have unit testing to cover this functionality.

These unit tests execute and pass on an OS X machine but we see SQLite related errors when running them on Windows 8 (64-Bit) VM (this acts as a slave within out CI infrastructure).

The error we see comes from NUnit (2.6.4) when the tests run

ProcessModel: Default    DomainUsage: Single
Execution Runtime: net-4.5
Unhandled Exception:
System.BadImageFormatException: Could not load file or assembly 'App.Core.Tests, Version=1.0.5900.25009, Culture=neutral, PublicKeyToken=null' or one of its dependencies. An attempt was made to load a program with an incorrect format.
File name: 'App.Core.Tests, Version=1.0.5900.25009, Culture=neutral, PublicKeyToken=null'

Server stack trace: 
at System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String  codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
at System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
at System.Reflection.Assembly.Load(AssemblyName assemblyRef)
at NUnit.Core.Builders.TestAssemblyBuilder.Load(String path)
at NUnit.Core.Builders.TestAssemblyBuilder.Build(String assemblyName, Boolean autoSuites)
at NUnit.Core.Builders.TestAssemblyBuilder.Build(String assemblyName, String testName, Boolean autoSuites)
at NUnit.Core.TestSuiteBuilder.BuildSingleAssembly(TestPackage package)
at NUnit.Core.TestSuiteBuilder.Build(TestPackage package)
at NUnit.Core.SimpleTestRunner.Load(TestPackage package)
at NUnit.Core.ProxyTestRunner.Load(TestPackage package)
at NUnit.Core.ProxyTestRunner.Load(TestPackage package)
at NUnit.Core.RemoteTestRunner.Load(TestPackage package)
at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Object[]& outArgs)
at System.Runtime.Remoting.Messaging.StackBuilderSink.PrivateProcessMessage(RuntimeMethodHandle md, Object[] args, Object server, Object[]& outArgs)
at System.Runtime.Remoting.Messaging.StackBuilderSink.SyncProcessMessage(IMessage msg)

Exception rethrown at [0]: 
 at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
 at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
 at NUnit.Core.TestRunner.Load(TestPackage package)
 at NUnit.Util.TestDomain.Load(TestPackage package)
 at NUnit.ConsoleRunner.ConsoleUi.Execute(ConsoleOptions options)
 at NUnit.ConsoleRunner.Runner.Main(String[] args)

Is this related to the fact that were using 64-bit windows?