Magento 1.x: Field Map Transform Error
The issue relates to the attributes that contain special characters that have been added into the fields.
magento-1
Special characters are used for computer programs and might break the program if used out of context. In general, all Stock2Shop fields should only contain alpha-numeric characters (letters from a-z and numbers 0-9) and basic punctuation. Avoid slashes and other characters.
Note, if you are copying text from other sources, you should always add it to a text editor to remove any styles that may have been copied.