php errors with phpfreechat-7.x-1.0-alpha2.tar_.gz module

Hello Tessa,
I tried your module phpfreechat-7.x-1.0-alpha2.tar_.gz (I uninstalled phpfreechat module before I tried your module)
but it gave me a lot of errors and some of my pages stopped to work.
Plus I found these errors in watchdog:

TYPE php
DATE Thursday, 2 April, 2015 - 23:27
USER admin
LOCATION http://nove.somvprahe.sk/node/add/phpfreechat
REFERRER http://nove.somvprahe.sk/node/add/phpfreechat
MESSAGE PDOException: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ')' at line 1: SELECT nid, phpfreechat_enabled, phpfreechat_title, phpfreechat_channels FROM {phpfreechat} WHERE nid IN(); Array ( ) in phpfreechat_node_load() (line 222 of /var/www/somvprahe.sk-nove/sites/all/modules/phpfreechat/phpfreechat.module).
SEVERITY error

TYPE php
DATE Thursday, 2 April, 2015 - 23:24
USER admin
LOCATION http://nove.somvprahe.sk/admin/config/content/phpfreechat
REFERRER http://nove.somvprahe.sk/admin/config/content/phpfreechat
MESSAGE Notice: Undefined index: server_script_url in phpfreechat_settings_form() (line 504 of /var/www/somvprahe.sk-nove/sites/all/modules/phpfreechat/includes/phpfreechat.admin.inc).
SEVERITY notice

almost every page on the web somewhere connected with content is giving me the error: "The website encountered an unexpected error. Please try again later."
When I disabled the module, everything started to work correctly.

thanks
Igor