Basecamp Routing on lastest Australian Maps has gone mad!

Have you ensured the latest maps are actually selected on the unit? If so have you tried doing a recalculation on the unit?

Looks to me like your Nav5 is simply using the Basemap.

Yes the latest maps are selected on both basecamp and the Nav. I'm zoomed right in to a section of country road to show clearly what's happening. It's definitely not the global basemap. I've got no other maps on the unit. In Australia they won't let you install the maps into internal memory.
There are other sections on the route which look like tangled fishing line. I can do the route on a Windows machine and get it to work, but not on the Mac OS 10.10.

Are you using BaseCamp to Transfer the Route to the NAV5? If so, try Exporting the Route to GPX on your Mac and then copy the GPX file to your NAV5/GPX folder. You could also post a Route (it can be simple) that is doing this on your NAV5 and we can take a look at the code.

I dragged the routes to the microSD card and then imported them into internal memory with the trip app. I did notice that it wanted to break up one of the routes because of too many via points. I have routed this trip a few times in previous versions of basecamp - never saw that.
By the way, the screen shot is from the route on the Nav 5 using the maps in the unit which is plugged in. I tried on my Windows machine I can get the route to work. Something seems to happen once the route is imported into the device with the trip app.

Do you mean the route from internal memory or from basecamp original? Do you have the Australian maps?

I remember similar behavior a few basecamp Mac versions ago. Straight lines, little right angle excersions from the route, etc.

It would seem to me that if you can transfer a route from WIN-BC and it works but when you transfer the same route from MAC-BC is doesn't, that the problem is with the MAC-BC route file and not the NAV5.

Please try this in your MAC-BC, create the route and then select the List and use the Transfer to device option. At the same time if you would post the GPX file here we can take a look at it.

BTW, I do have Australia Maps.

Thanks drtbyk. I'm creating the routes from scratch in Mac or Windows setup, l am not transferring routes between systems. I'll try wiping everything from basecamp and the nav5, plus doing a hard reset on the nav5.