Update field before saving

After digging into your code, I found the solution myself.

Here's the solution for those who need:

// there's a filter to alter value before post being saved
add_filter ( 'rwmb_NAME_value', 'somefunction' );

function somefunction() {

// get data
$get_data = isset( $_POST['SOMEKEY'] ) ? $_POST['SOMEKEY'] : null;

// do something with your data, multiple by 100 for instance
$modified_data = $get_data *100;

// return the modified data
return $modified_data;
}

Anyway thank you for crafting many hooks for ease of use.

Cheers.