I have noticed that there is a small bug in the "User Mapping" section in the admin interface. It's related to the autocomplete seach box in the box labelled "Integrate to a suggested match:" in each row. Whatever I type, it returns me all users; the search term is not applied. I had a look at the code and I think I fixes. Please see the fix below and please include it in the next version if you find it sufficient. Thanks.
File user-mapper.php, class WPU_User_Mapper, line 57:
'showLike' => '',
...should be changed to:
'showUsersLike' => '',
The array item showLike set to be empty by default will always overwrite the method argument showLike when function extract is called on line 61. Once the array item is renamed to showUsersLike nothing will overwrite the parameter and the correct value will be set on line 73.