Hello @nasrul ,
I am very glad to announce you that at the latest version (3.0.16) we now have the ability to take the master_id at insert/update/clone forms.
A simple example of how to do that in the detailed CRUD is the below code:
$crud->fieldType('customerNumber', 'hidden');
$crud->callbackBeforeInsert(function ($stateParameters) {
if (!empty($_POST['master_id'])) {
if (is_numeric($_POST['master_id'])) {
$stateParameters->data['customerNumber'] = $_POST['master_id'];
} else {
throw new InvalidArgumentException("Invalid argument for the field 'master_id'");
}
}
return $stateParameters;
});
So basically you need to use the callbackBeforeInsert and make sure that you have the fieldType as hidden so the insert form will not filter it.
If you are using Composer then I have more good news for you since now we have moved to our private composer server. In short that means that you no longer need to download any zip file for update 
For more you can check the blog post: Grocery CRUD Private Composer | Grocery CRUD Blog
Let me know if that worked for you.
Regards
Johnny