Hi,
Just wanted to let you know that I took a peek at your code and already solved the problem I described above.
To solve it:
On line 525 in testimonial-rotator.php
change
$global_rating_number = floor($global_rating / $post_count);
to
$global_rating_number = ($global_rating / $post_count);
$global_rating_number = round($global_rating_number,1);
and on line 530 (531 after you added the line above)
remove .0
from
echo "\t<div class=\"rating\">{$global_rating_number}.0</div>\n";
Now it gives the right rating with one decimal.
I hope you can implement this change in the next update.
Thanks!