Problem with Paymill Plugin

-- HikaShop version -- : Business 2.3.4
-- Joomla version -- : 3.3.1
-- PHP version -- : 5.3.10

Hi,
i used the paymill plugin from github.com/paymill/paymill-joomla-plugins/
but ist does not work right.
I can enter credit card data but then everything stops and nothing happens.

now i'm interested in finding a developer who can fix it.
Please contact me if you are interested and let me know the price.

kind regards,
romana