woocommerce variable products max variations

Hello,
we use Woocommerce v 2.0.13
WP Version: WP 3.6
PHP Version: 5.3.27
and have a situation when trying to link variations for product like the example below.
Product with variation
quality: of two values : A – B
and variation size of 13 values: 44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66
if you link all variations it gets it starts behaving upnormaly after updating the change. It seems to not saving prices, not saving all variations correctly along with the prices.
Tested it and it behaves perfect if you link all variations up to size 63 (but this is not a solution of course since you have to leave behind 3 more sizes necessary for the shop).

Any solutions or workarounds please?

https://www.ads-software.com/plugins/woocommerce/