I'm using Joomla 2.5.14 and K2 2.6.7
With that configuration, I should be able to use K2 extrafields aliases with :
$this->item->extraFields->EXTRAFIELDALIASHERE->name
and
$this->item->extraFields->EXTRAFIELDALIASHERE->value
as it is explained here
getk2.org/blog/item/1068-k2-v262-now-available
to display a specific extra field.

Is there a way to use that code in a K2 Tool module (with the personalized code option) so I could display my extra field in a specific location without creating a K2 module sub template?

K2 Tools is not intended to display item lists. You need to use K2 Content istead in order use this snippet.

What I would like to do is to be able to display some K2 item data (like title, main text, image gallery…) in the content location of the page, while displaying some specific data of the same K2 item in other locations of the page using multiple K2 BNR Content modules.
This works fine but I can't choose witch specific extra field to display. With K2 BNR Content module, It's all or none.
I saw that since K2 v2.6.2 there's a way to call a specific extra field using its alias in PHP code ($this->item->extraFields->EXTRAFIELDALIASHERE->name ). But this code seems to be used in a sub template. As I don't know much of PHP language and how to create and use sub templates, I would like to know if there an easier way to use that code in a module.
Thanks for your help.

This cannot be done without a K2 Content module.

The code is pretty straight forward (it is a c/p snippet) and you shouldn't have any issues creating a new subtemplate.

Please provide the "specific" code necessary to display the Extra Field for the item page that user is on.

When I attempt to use the standard code, it renders a blank screen:
<?php echo $this->item->extraFields->ExtraFieldAlias->value; ?>

I also tried using the BNR module - which only shows all extra fields (as mentioned by Iannis Camillieri in a previous post). When I tried using the module, it rendered a blank screen.

What is the "specific" code needed to utilize a K2 Content module to displaying an Extra Field?

This code is not intended for the BNR module.
In the K2 Content module you do not need $this.

Krikor Boghossian wrote: This code is not intended for the BNR module.
In the K2 Content module you do not need $this.

<?php echo $item->extraFields->ExtraFieldAlias->value; ?>

Tried the following in my default.php template file but doesnt display anything...

<?php
if (!isset($item->extraFields))
{
$item->extraFields = new stdClass;
}
foreach ($item->extra_fields as $extraField)
{
$tmpAlias = $extraField->alias;
$item->extraFields->$tmpAlias = $extraField;
}
?>


<div class="moduleItemExtraFields"><span class="moduleItemExtraFieldsValue"><?php echo $item->extraFields->JobID->value; ?></span>