MvvmCross Rio Binding in Windows 8.1 - binding

Question

I'm making a project using Xamarin + MvvmCross and I've encountered a problem while trying to make rio binding working on Windows 8.1 Store View app.
I've added references to BindingEx for Windows plugin, FieldBinding plugin and ofc to Hot-Tuna Starter Pack. Unfortunately, every time I'm trying to run my app I'm getting the error:
"Failed to assign to property 'mvx.Bi.nd'. [Line: 15 Position: 38]"
(Windows.UI.Xaml.Markup.XamlParseException)
Firsty, I thought that there must be something wrong with my core, so I've created a new project (core & Store UI) but it's all the same... But in WP8 UI project similar approach works like a charm..
Im getting the error using for example this piece of code:
In my core:
using Cirrious.MvvmCross.FieldBinding;
using Cirrious.MvvmCross.ViewModels;
namespace App1.Core.ViewModels
{
public class FirstViewModel
: MvxViewModel
{
public INC<string> Sample = new NC<string>("Hi There!");
}
}
In my Store UI:
<views:MvxStorePage
x:Class="App1.Store.Views.FirstView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mvx="using:mvx"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:views="using:Cirrious.MvvmCross.WindowsStore.Views"
mc:Ignorable="d">
<Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
<StackPanel>
<TextBlock FontSize="55" mvx:Bi.nd="Text Sample" />
</StackPanel>
</Grid>
</views:MvxStorePage>