WooCommerce and Variable product / Variations problem

Hello all experts ??

So I was reading quite a lot this forum regarding the same issue that I have but without any luck. So here I go, too…

WP 3.8 with Woocommerce 2.0.20 all 22 plugins on or off doesn’t matter.
Running on child theme without any other problem.

– Made Attributes
– Add new product
– Select Product data: “Variable product”
– Add Attributes with no problem
– Save
– Click on Variations
– Want to add new product but button “Add Variation” is dead! Nothing. Nada!
The same story on “Link all Variations” button.

WooCommerce Status Report all green:

WC Version: 2.0.20
WC Database Version: 2.0.20
WP Version: WP 3.8
Web Server Info: Apache
PHP Version: 5.3.28
MySQL Version: 5.5.34
WP Memory Limit: 256 MB
WP Debug Mode: No
WP Max Upload Size: 64 MB
PHP Post Max Size: 64 MB
PHP Time Limit: 0
WC Logging: Log directory is writable.
Default Timezone: Default timezone is UTC
fsockopen/cURL: Your server has fsockopen and cURL enabled.
SOAP Client: Your server has the SOAP Client class enabled.
WP Remote Post: wp_remote_post() was successful – PayPal IPN is working.

I really need some expert to help me out. I have no other idea what to do or what to report for as much information as possible.

Thanks in advance!