Styles from a ResourceDictionary is preventing all other functionality - xaml

Question

UPDATE: I moved the TextBox's style to the phone:PhoneApplicationPage.Resources tag and it behaves exactly the same way so it turns out that is not the fact the I am using a ResourceDictionary what is causing the problem but that there is something wrong with the way I am defining the style.
I just started playing around with ResourceDictionaries and I really like them but when I tried to use them on my application everything stopped working.
First the following TextBox:
<TextBox Grid.Column="1"
Grid.Row="0"
x:Name="Value"
InputScope="Number"
TextAlignment="Right"
TextChanged="OnValueTextChanged">
<TextBox.Style>
<StaticResource ResourceKey="InputTextBox" />
</TextBox.Style>
</TextBox>
Update: I have updated the ResourceDictionary per XAMeLi's answer and now I see the borders but it would seem as the TextBox does not have any background but, when I click on it nothing happens as if the TextBox is not even there. Then by pure luck I noticed that if I click on the bottom border the numeric keyboard would pop up as if the TextBox is too small or hiding below the border element. I tried modifying the TextBox height to no avail. This is driving me crazy.
Then the ListPickers are even worse:
<toolkit:ListPicker
Grid.Column="0"
Grid.ColumnSpan="2"
Grid.Row="1"
x:Name="CategoriesPicker"
HeaderTemplate="{StaticResource ListPickerHeaderTemplate}"
FullModeItemTemplate="{StaticResource CategoriesPickerTemplate}"
ExpansionMode="FullScreenOnly"
BorderThickness="0"
Padding="0"
Margin="0"
SelectionChanged="OnCategoriesPickerSelectionChanged">
<toolkit:ListPicker.Style>
<StaticResource ResourceKey="ListPickersStyle"/>
</toolkit:ListPicker.Style>
</toolkit:ListPicker>
When the Style is in it won't even bind the data I'm giving to it.
The file with the ResourceDictionary looks like this:
<ResourceDictionary
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit">
<Style x:Name="InputTextBox" TargetType="TextBox">
<Setter Property="BorderThickness" Value="0"/>
<Setter Property="Margin" Value="-12"/>
<Setter Property="Height" Value="50"/>
<Setter Property="Background">
<Setter.Value>
<LinearGradientBrush StartPoint="0 0" EndPoint="0 1">
<GradientStop Color="DarkGray" Offset="0"/>
<GradientStop Color="DarkGray" Offset=".3"/>
<GradientStop Color="LightSlateGray" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="TextBox">
<Border
BorderThickness="2"
Margin="15"
CornerRadius="3">
<Border.BorderBrush>
<LinearGradientBrush StartPoint="0 0" EndPoint="0 1">
<GradientStop Offset="0" Color="DarkGray"></GradientStop>
<GradientStop Offset="0.3" Color="DarkGray"></GradientStop>
<GradientStop Offset="1" Color="LightSlateGray"></GradientStop>
</LinearGradientBrush>
</Border.BorderBrush>
<Border
BorderThickness="2"
CornerRadius="3">
<Border.BorderBrush>
<LinearGradientBrush StartPoint="1 1" EndPoint="1 0">
<GradientStop Offset="1" Color="Gray"></GradientStop>
<GradientStop Offset="0.3" Color="DarkGray"></GradientStop>
<GradientStop Offset="0" Color="DarkGray"></GradientStop>
</LinearGradientBrush>
</Border.BorderBrush>
</Border>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Name="ListPickersStyle" TargetType="toolkit:ListPicker">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="toolkit:ListPicker">
<Border
BorderThickness="2"
Padding="0"
Margin="10"
CornerRadius="3"
Background="DarkGray">
<Border.BorderBrush>
<LinearGradientBrush StartPoint="0 0" EndPoint="0 1">
<GradientStop Offset="0" Color="DarkGray"></GradientStop>
<GradientStop Offset="0.3" Color="DarkGray"></GradientStop>
<GradientStop Offset="1" Color="LightSlateGray"></GradientStop>
</LinearGradientBrush>
</Border.BorderBrush>
<Border BorderThickness="2"
CornerRadius="3">
<Border.BorderBrush>
<LinearGradientBrush StartPoint="1 1" EndPoint="1 0">
<GradientStop Offset="1" Color="Gray"></GradientStop>
<GradientStop Offset="0.3" Color="DarkGray"></GradientStop>
<GradientStop Offset="0" Color="DarkGray"></GradientStop>
</LinearGradientBrush>
</Border.BorderBrush>
<toolkit:ListPicker
BorderThickness="0"
Padding="0"
Margin="0">
<toolkit:ListPicker.Background>
<LinearGradientBrush StartPoint="0 0" EndPoint="0 1">
<GradientStop Offset="0" Color="DarkGray"></GradientStop>
<GradientStop Offset="0.5" Color="DarkGray"></GradientStop>
<GradientStop Offset="1" Color="LightSlateGray"></GradientStop>
</LinearGradientBrush>
</toolkit:ListPicker.Background>
</toolkit:ListPicker>
</Border>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ResourceDictionary>
Please, somebody explain to me what am I doing wrong.

Answer 1

Inside your ControlTemplates there are the controls them selves, i.e. control template for text box is holding a TextBox. This is not how control templates should be used. Use Blend or VS11 to extract the default style for each control (I'd recommend doing it in a new clean solution) and then change the visual appearance.

Answer 2

You should be able to reference the style just like any other property, e.g.:
<TextBox Style="{StaticResource InputTextBox}"/>
And try setting your Style first, then any settings you want to override, e.g.:
<TextBox Style="{StaticResource InputTextBox}" TextAlignment="Right" />

Answer 3

You should use x:Key instead of x:Name in ResourceDictionary:
x:Key and x:Name are not identical concepts. x:Key is used exclusively
in resource dictionaries. x:Name is used for all areas of XAML. A
FindName call using a key value will not retrieve a keyed resource.
However, Silverlight 5 can use an x:Name (or Name) attribute as the
substitute resource key for a resource item if no x:Key exists on the
item.
and as soon as Windows Phone is far from Silverlight 5, you can not use x:Name in the dictionary.