Delete the route you modified in TANE.
Here's a better solution, which I forgot about last night being quite late as it was.
Open up your route from Fishlipsatwork in TS12 and make a slight change, i.e., add a tree and then delete.
Save the route, meaning it's cloned now under your ID. I've done this and called the route FOR MERGING, or something similar.
Import the clone into TANE.
This will work 100% of the time.
The other method is to take the original and rename the island files to mapfile by opening the route for editing in Content Manager, but this has to be done before any other editing in TANE. I think the TS12 method is easier.