Hi Carles,
The interim patch is not the same as version 3.1. There has been a lot of work done since we sent you the patch.
From version 3.0, updates have been made easier with the msi package, it should not be difficult to update to version 3.1 from version 3.0 or from the interim patch.
In the upcoming version 3.1, we add tools to easily configure your clients and servers. If anything went wrong when updating to 3.1, you would be able to correct any configuration in a couple of clicks.
I believe version 3.1 will be released next week, it's up to you to decide whether you can wait a week or not.
Regards,
Marien Monnier
Enesys