No, you've not got the wrong maps. the green dots basically mean "unsurfaced route" which most of the lanes fall under. The orange dotted ones are similar, but vehicles can't use them, (you'll find these in parks, canal bankings etc) There are those with the ++++++ symbol, these are as you know BOATS.
You need to check on *TRAILWISE*
http://www.trailwise.org.uk find the lane on their map page, then check on it's latest standings. I find that Trailwise is usually up to date with any TRO's etc.
You will find lanes with lots of information, some with a little, and some with non at all as no-ones added anything.
If you're a member of GLASS or CRAG, then you contact the admin on Trailwise, and you'll be able to search much more information on the lanes, and can add information yourself.
regards
jim