funnnyfarm,
In content manager, go to "my content" or "installed" and highlight and right click on the route you want to fix. Either click on view faults and warnings or click on missing dependencies and see what is shown. The red exclamation mark indicates an asset fault, (you can ignore the yellow exclamation marks) and the yellow jigsaw piece with a question mark in it is for missing dependencies. If it's just missing dependencies it will show you which they are. Anything with the DLS symbol next to it will be available on the DLS, but anything with a black question mark means that it is unknown and is possibly available via google searching or payware sites etc. Click on "view in main window" and anything with the DLS symbol you merely drag into to search window and it will instal it for you (providing you have the necessary version to support it).
Other items require a bit of effort but in the main I've found that with persistence you can find most things.
Hope I've been some help.
Dan.