Lidar is probably available if you want a real basemap.
But here is a screenshot from Strava Heatmap (I hope of the right area). Unfortunately, it's very difficult to get georeferenced images from Strava since their bad press about a year ago. Interestingly, most of these are from MTB gps tracks, and it's likely MTB trail builders change things a lot. But this should be a good start for "just trails".Batchelor_St_Strava_Heatmap_not_georeferenced.png
OCAD 9 and earlier might have issues with PNG format files.
It used to be possible to update OpenStreetMap using the Strava Heatmap tracks. For twisty stuff like this, it's a pain, but you end up with vector format trails that can be imported into OCAD. If anyone has any ideas about how to get Strava to fix this, please let me know. I've spent hours and hours trying, and I can't even find a mailing address for Strava.