Create a custom field with users and another one using records from a CPT.

Hi,
I'd like to create to custom fields with Types:
1. A select field retrieving users as values exactly like for this ticket:
http://wp-types.com/forums/topic/types-create-a-custom-field-and-have-a-dropdown-of-users-as-value/
But I just don't know where to put this code?

2. An other select field will make appear values (precisely the post Title with link) from an other CPT created with Types.

Thanks for your help,
Julien