Migration failed with source plugin exception: SQLSTATE[42S22]: Column not found: 1054 Unknown column
On Drupal 6 running CCK, the database field names are different from the CCK field names. 

In my test site running Drupal 6, I created the following CCK fields:


field_code_page (text)
field_co_author (user reference)
field_book_list (node reference)




The database table created from CCK for the content type containing those fields has the following database fields:


field_code_page_value
field_co_author_uid
field_book_list_nid




It is rather probable the database field is named ctp.field_titul_pred_jmenem_value. To be sure, you should check the database table, as the database field could have a different name, basing on the type of the CCK field.