Bummer. Well, that's why I restrict myself to stuff that's freeware AND on the DLS, makes it easier for the computer clueless to install and don't require playing hunt the KUID to make it work. I have a couple of Jointed Rail PO&N F7s on the DLS, they require dependencies that are only available from Jointed Rail, so I don't use them in sessions. More critical with TS12 multiplayer now, a TS12 multiplayer session wouldn't work at all with those locos.
While I was uploading, took some pictures, little tutorial for whackos like me who start skinning and can't stop without a 12 step program, how do I keep track of what I've uploaded and what I haven't yet?
First step is in the TS2010 or TS12 folder, find trainzoptions.txt and open in Notepad;
Add the line -ShowKuids at the bottom and save, now the KUID number of every asset you place in surveyor will be shown at the lower right corner.
Start with create new session, so the session is empty except for what you put in it. Set the content filter for My Content, then go down the list of your stuff - if it has a white KUID it's on the DLS, a red KUID means it's not. So place all recent repaints with the red KUID numbers, double check to make sure they're all red KUIDs;
Then save the session and exit. Open content manager;
Select the new session and right click, view dependencies, then hit the View in main list button.
Sort the list by clicking the Author button at the top, leaving out built in stuff like the coal and water and the route itself, you now have a list of what you haven't uploaded yet. I got a pretty slow DSL connection, so I split that into three sections before saving to CDP, then uploaded the CDP files to the upload page. I'd add a link for that but apparently they're tightening loose screws again cuz I get a timeout error on it now, but it's something like 
https://www.auran.com/planetauran/YC_main.php?ProfileGroupID=0&Action=UploadListing