These nuns, although doing allot of good by helping the poor and undertaking important ground level work (charity) are doing a great amount of harm by spreading false doctrine and question the 'Authorities'.
The ' Authorities' in the Catholic church have been given the power to 'bind and loose' which makes the successor of Peter correct and truthful in everything he says/proclaims on behalf of Jesus Christ. It's not a bunch of policies to control and grow the Catholic church as obviously, judging by the opposition against some church teaching, it doesn't work because its received as being outdated and old fashioned.
The truth is that the Catholic church is not here to 'keep up with the times' or to please everyone. They are here to guide morally and help us to do God's will which is (bound and loosed) there will, one and the same. The church is one and allowing the nun's to spread their own opinions doesn't help us to be one.
Let's just be clear that in today's society, being a Catholic is not easy. To be a good witness of Christ you need to be courageous and defiant against the popular misguided opinion. We need to avoid attractions of a sexulised world and just generally die to ourselves and not always do what we want just because we feel like it. It's not easy but it's truth and it will bring great rewards of unimaginable measures.
Just like any other institution, we have our problems and are under constant renewal. We all, as Catholics, acknowledge that there have been unspeakable cruleties against chilldren and poor mistakes made by church officials. I would just like to point out to every body who criticises us that in the Catholic church when we make a mistake we repent and suffer and then we move on to be better people and a better institution. With Christ we are better placed then any other institution to renew ourselves effectivley and become what Christ wants us to be.
To the laity and Priest's and Nun's who want to speak out and challenge church teaching please remember what church you are actually in and where the book stops (at the successor of Peter on behalf of the son of God) you have absolutley no right to challenge this as you are challenging Jesus. Let us be one in the face of every opposition and let us radiate God's light in this darkened world.
May the Lord convert all our hearts in the Catholic church to make us one in him.
In God's Love