In CM right click on the asset to update, choose View Asset Version.
Next click on View in Main List and download the one with the DS icon.
The list should then change with the current version in the snooze mode and the update will have the Installed Icon beside it.
Sometimmes an asset will not update, so in that case you need to write down the kuid for the updated version and the current version. The difference will be the last number (xxxxxxx:xxxxxx:1)or (Kuid: or Kuid2

Now choose Edit, Edit in Explorer.
Locate the Config.txt file and open it.
Look for the Current Version kuid
When you find it change it to the Updated Version.
Check all the way through because it may be listed more than once.
Once you have done it, File,Save and Exit .
Return to the asset listing.
Commit the asset
Cheers,
Mike