Puzzled, with regards to your statement:
I also agree clarity about the law is vital, but it remains an unfortunate fact that, where aspects of the law are disliked, insistence on adherence will be presented as an attack on values
It's all about the approach. There is a group who will feel that it is their absolute right to be hostile and to ignore the law and try to circumvent it by any means they can. There is also a group which will go out of their way to show how accepting they are of British laws because their main priority is being accepted here and not practising their religion.
But then you have that large group in the middle whose religion is their priority but who understand, or have the potential to understand, that while living here they have to comply with the laws and live in peace with others. When it comes to this group, they way you approach sensitive and controversial issues makes a huge difference.
Pointing out that they have to comply with the law is not so much the issue. The issue is that this is frequently accompanied by value judgements and an insistence that Muslims should be persuaded into changing their thinking to see British laws as progressive and their own attitudes as regressive. This is problematic and to be honest I'm shocked that language like 'regressive' was used in the report.
For example, the review highlights concerns around polygamy. Polygamy is already against the law in the UK, so that's all that needs to be stated. Why do we get several paragraphs going on about how allegedly harmful polygamy is? All that does is alienate people who are already complying with the law about it. We don't have to agree with the law in order to comply.
If someone comes to me asking questions and expressing concerns about non-compliance with polygamy laws in a respectful manner much like you have been doing on this thread, it opens up a dialogue and allows for interaction.
But if someone comes along using strong negative language about polygamy and demanding that I condemn it in principle and change my thinking, that is just going to put me on the defensive instantly and make me far less likely to feel comfortable with the person or want to engage in dialogue. It's actually highly offensive to Muslims to suggest they should be critical of polygamy in principle. It's permitted in our religion, many of us have family members outside the UK in polygamous marriages, and our Prophet (peace and blessings of Allah be upon him) and his companions used to marry more than one wife.
I'm not calling for polygamy to be legalised in the UK, but the approach taken needs to be sensitive to this context. That's why I'm saying that the focus should be on clarifying exactly what laws and guidelines Muslims need to comply with while still allowing them freedom of thought. Of course there are a vocal minority who will resist adhering to the laws, but there are also many people like me who are not seeking to overturn nor circumvent the laws, but feel very worried that our freedom of thought and belief seems to be under attack.