This footpath allowed my route planner to plot a cycling track along it - which would be illegal.

At this point the white road NW to the buildings is not part of Ruscombe Lane, but is LEIGH GATE LANE. The route of the brown dot dash line heading NE right up to Ridgeback Lane is all part of Ruscombe Lane, as is the white road S into W Milton. This is confirmed on FMS https://www.findmystreet.co.uk/map search for USRN 43201293 but also on all other maps. NB Devon Explorer calls it Runscombe but this is a typo, you can select historical maps to see the correct spelling from the 1800s https://gi.dorsetcouncil.gov.uk/dorsetexplorer#map=17.18/50.77160/-2.70306/0&layers=175/100/100//,85/100/100//,2/100/100//,15/100/100//&basemap=1/100/100

There is a through route here that can clearly be seen on aerial photography and can also be found on DCCs Dorset Explorer selecting Public Transport and Unclassified Roads. See https://gi.dorsetcouncil.gov.uk/dorsetexplorer#map=16.55/50.92560/-2.47104/0&layers=85/100/100//,1598/100/100//&basemap=1/100/100
It is fully legal for all traffic as an Unclassified Road, but is a 'green lane' and so should be annotated to keep it from being used by sat navs to route normal road users as you need a vehicle with off-road capability. It's also shown on FMS - See https://www.findmystreet.co.uk/map?gclid=CjwKCAjw0dKXBhBPEiwA2bmObXMelI05_367BYPNCGE4hGPzRaiZM0KBb72aujq-uzngVI9zNFo1ZhoCoOUQAvD_BwE
The continuation S of the A3030 to Down Lane should also have the same attributes.

Byway Open to All Traffic CL14/54 is completely missing from the map here. It's legal for all traffic but you couldn't get a car down it so make sure it has the right permissions so sat navs don't start using it! Route is a straight line just NE of the green line on the map now, from the junction of Greenhouse and Howgrove to the bend in green lane just N of the green line. See https://app.bathnes.gov.uk/webforms/maps/?base=Ordnance%20Survey&center=51.365112936177006,-2.6902261376380925&zoom=18&categories=highwaysandtravel,highwaysandtravel_adoptedhighway,highwaysandtravel_publicrightsofway&wfslayers=mlyr-702749,mlyr-702750,mlyr-702751,mlyr-702754,mlyr-702753,mlyr-702732,mlyr-702752,mlyr-354381,mlyr-354638,mlyr-354409,mlyr-354630,mlyr-800194,mlyr-798597,mlyr-799028,mlyr-800017,mlyr-800219,mlyr-800222&wmslayers=mlyr-354398,mlyr-2523873

This is called "The White Bridge" and it is now fully open to motor traffic. You can search online to see this but we rode over it today. Please adjust so that open map based sat navs will use it.

This set of steps allows motor traffic to route up it on open map based sat navs!

This junction is wrong. See https://www.google.com/maps/@51.6119991,-3.4098023,3a,75y,302.13h,90t/data=!3m7!1e1!3m5!1sev11k6WhxKmX-uuo__YI3g!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fcb_client%3Dmaps_sv.tactile%26w%3D900%26h%3D600%26pitch%3D0%26panoid%3Dev11k6WhxKmX-uuo__YI3g%26yaw%3D302.1349754588122!7i16384!8i8192?entry=ttu&g_ep=EgoyMDI1MDQxMy4wIKXMDSoASAFQAw%3D%3D
When heading NNW on the A4058 sat navs will route a R turn but this junction is no right turn. You have to continue to the roundabout and come back heading SSE and make a L onto the B4278 on a slip road that isn't shown on your map.

Tinker's Lake access road from A38 extends to where I've put the marker. See FMS for confirmation.

The lane just to the W ends exactly where I've put the marker, it does not connect to the A38 and there is not a tunnel under to connect to the Tinker's Lake access road either. FMS correctly maps this street and Street View clearly shows the A38 barriers are unbroken.