And what's the best way to get actively involved, MHM?
DUnno about MHM, but I drive all the lanes in my area and email/telephone/snailmail councils when they get blocked. Whenever or wherever I drive a lane and find it blocked I abate the blockage where possible and inform (email/tel/letter) the appropriate council/public highways dept.
I attend meetings when I can, local council has a public forum which I also attend when I can.
I've been to meetings on proposed TRO's in Norfolk, Salisbury, Derbyshire, North Yorkshire and Wales when TRO's have been proposed on lanes I've driven. I also write letters wenever I feel a TRO is wrong, as in the case to TRO Roych etc .. I did for Chapelgate and others too.
One thing that helps at many public meetings is proof that you have actually driven or used a green lane. So I often take pics of very recognisable features along a lane to 'prove' people still actually drive it .. it's one reason I used to keep my Disco as near standard looking as possible ... a Disco is recognised by many bobbles as a 'Chelsea Tractor' that's only off-road on tescos carpark. OK, it's a bit rougher-looking now but the principle still stands .. it ain't a challenge truck!!
I don't often crow about what I do, I normally just do it. I've mentioned a couple on here in the past where I've had good results .. but mostly mine's just a small effort ..
Whenever a TRO is proposed we need as many opposers to the proposal as possible. Trouble is, we need them to oppose it 'properly' by writing letters or emails (many templates on t'web to use if people aren't confident about writing to councils or authorities) .. not with temper tantrums and 'shows of strength', but with reasoned debate and often compromise .. like the voluntary scheme(which was mostly observed) on Stanage, for instance ..
OTOH, when all else has failed and a TRO is made permanent, then maybe we could do stuff like the ramblers did originally, mass trespasses and vocal/vehicular protests .. but they need doing properly, not ad-hoc, and they do carry some risk ...