Highend and WPML plugins are killing my

I purchased this theme because your promotional banners said it is WPML compatible. I purchased it from Mojo themes because my webhost Hostgator is partnering with them, so I thought Mojo themes should be optimised for Hostgator webhosting.

I tried to investigate what is wrong with WPML and found out that WPML > Support > Debug Information , outputs some strange error:

<br />
<b>Warning</b>: json_encode() expects exactly 1 parameter, 2 given in <b>/home2/maxzb/public_html/ugodnavrata.eu/wp-content/plugins/sitepress-multilingual-cms/inc/functions-debug-information.php</b> on line <b>143</b><br />

So it is logical that there must be some incompatibility with Highend theme and WPML plugins.

I just loaded Demo content, installed latest WPML plugins and site is sooo slow that is killing my webhosting. I can let you login to my WP Admin of this site, so you can see, just tell me where to post login details. Thank you.

My domain: ugodnavrata.eu
Admin: http://ugodnavrata.eu/wp-admin

WP version: latest 4.0
WPML versions:
Plugin Name Status Active Version
WPML Multilingual CMS Installed Yes 3.1.7.2
WPML CMS Nav Not installed No n/a
WPML String Translation Installed Yes 2.0.9.1
WPML Sticky Links Not installed No n/a
WPML Translation Management Installed Yes 1.9.6
WPML Translation Analytics Not installed No n/a
WPML XLIFF Not installed No n/a
WPML Media Installed Yes 2.1.6
WooCommerce Multilingual Not installed No n/a
JigoShop Multilingual Not installed No n/a
Gravity Forms Multilingual Not installed No n/a
CRED Frontend Translation Not installed No n/a
Installer Not installed No n/a

And I have your latest theme version. (Installed Highend and Highend child, I activated (use) child theme.)

I will add login details just say where should I send those to you.