Unfortunately as I see it, the staff at N3V did it the old easy way. Instead of thinking ahead, they chose the good old simple upload all because that's so much easier than picking what should be included and what shouldn't. You mean to say they can CTRL- or Shift-click to select assets?
Understandably, there are things that need to be locked if they are going to do that, however, this should be done as the choice of the original author. The content creator uploading a route or an asset to N3V for inclusion in the DLC packages, should state what items or whether an item should be locked. The Cornish route we received around Christmas a year ago is a good example of this and it shows it can be done. This route, although distributed through the DLC system, is fully editable just like any other route we've installed in the past. Then on the contrary, there are going to be locomotives, passenger cars, or wagons that the authors don't want tampered with. This is author's right to do that if they wish and rightly so.
I also feel we're being ripped off because content that's for sale elsewhere, such as Jointed Rail's routes, locomotives, and other assets, should not be locked if they are installed as part of the DLC system. Why lock up these assets in this version and not the other? This is very deceiving for customers because they see a route for sale on N3V's website that's also available on Jointed Rail's website without knowing that the route can't be altered. Why should the customer then go through hoops to remedy this and then purchase something twice?
Yes we can edit the DLC routes in TRS19 now, but the routes built-in or DLC should be fully editable, and by fully editable I mean being able to merge the routes into others and not this you can edit, but not merge. Merging routes is a big part of the editing, and a big part of the Trainzing experience we have enjoyed since the program's inception, and for many of us since at least TRS2004 arrived on the scene. If there are conditions about uploading merged routes, well that should be stated, however, make merging available again.
It's because of these issues, I am very reluctant to purchase or download any newly released DLC including routes for fear that assets will be locked out, or break something already installed. I have an install now that has what were once fully editable assets from Jointed Rail now locked and no longer the assets I originally installed. There is no physical difference between the assets other than the version number to force the non-DLC version into obsolescence. I found this out the hard way with some textures I have used for years that have now become PBR-textures when they became built-ins. I didn't discover this until one day while running a route when I discovered buried track and jelly-donut innards all over my route. Instead of enjoying my driver's session, I spent hours looking for non-PBR replacement textures that were similar to the ones I had chosen before, however, no matter how close these textures are, they are not the same as the originals.