I had the same trouble with a few extensions and this is what WooCommerce told me:
“I had a look at it and it seems the issue is with your theme, the theme is including what looks like the WooThemes updater and this causes the updater in the plugin to not load.
What you can do to get it activated is to switch your theme to twenty twelve, activate the plugin and then switch your theme back. I would also suggest you contact your theme developer and inquire about why they may be including WooCommerce specific functions like woothemes_queue_update which is causing it to fail.”
I switched to twenty twelve and was able to install the plugin. It seems like the plugin is now working fine. I don’t know if this is the same for your situation, but it may help.