My first custom module I found some code on the Drupal forum that solves a problem I have. Several users report the code works for them so I suppose I did not exactly get how to create a custom module. I followed the following steps:

Create a folder called i18nblocktran in sites/all/module and added two files:

i18nblocktran.info

; $Id$

name = Wysiwyg taxonomy translation
description = Displays the wysiwyg editor in the taxonomy term translation interface 
package = Nathan
core = 7.x 
files[] = i18nblocktran.module


and i18nblocktran.module

&lt;?php
function i18nblocktran_form_alter(&amp;$form, &amp;$form_state, $form_id){
  if($form_id == 'i18n_string_translate_page_form'){
    foreach($form['strings'] as $name =&gt; $field){
      if(preg_match('/blocks:block:[0-9]+:body/i',$name)){
        // Change textarea to text_format
        $form['strings'][$name]['#type'] = 'text_format';
        $form['strings'][$name]['#description'] = '&lt;br/&gt;';
      }
    }
    $form['#submit'] = array_merge(array('i18nblocktran_string_translate_page_form_submit'), $form['#submit']);
  }
}

function i18nblocktran_string_translate_page_form_submit($form, &amp;$form_state) {
  // Remove wysiwyg format because i18n cant handle it
  foreach($form_state['values']['strings'] AS $name =&gt; $field) {
    if(preg_match('/blocks:block:[0-9]+:body/i',$name)){
      unset($form_state['values']['strings'][$name]['format']);
    }
  }
}
?&gt;


Then I activated the module in the admin but nothing happened. What did I miss ?
Change line 4 in your .module file

foreach($form['strings'] as $name =&gt; $field){


with this

foreach($form['strings']['all'] as $name =&gt; $field){


It should do the job