The icons for those are in <trainz folder>/bin/CMPData/status.
As for the limited assets, you need to turn off the favourites feature.
You can do this from the in-game options, on the Surveyor Settings tab - the tickbox labelled 'only show favourite content' (or similar) needs to be unticked.
If the issue is also affecting routes, look for a yellow star on the Routes page - click it to turn it off.
Shane