Missing assets?

I have a route I've been working on for a couple of years. When I looked at it today in CM it shows as having missing assets.

I loaded it up in Surveyor and deleted missing assets. Saved it. Looked at it again in CM and it still shows one missing asset. Why might that be?

Firstly, if it didn't have missing assets yesterday, have you deleted or moved anything?

Possibly a dependency of one of the assets?
[possibly] The next step is to edit the config to remove the asset from the kuid listing and resave the confi file, then submit the change.

A note regarding Tony's second suggestion - from memory this only works until the route is next updated and saved in Surveyor which will then overwrite any changes made to the config file.

Shane