I really like watching my replays.. but it seems almost any update that comes up, either from S397 or the workshop, my older replays becomes messed up. I loaded a VEC replay from last month's Nurb race. The first time I loaded it, all I saw was zoomed in text where the replay should've been playing. I closed it and tried again, this time it loaded the track, but the incorrect car was showing (it was the car I had last driven, that was selected in the main menu). So, I assumed if I chose the correct car in the menu, it'll load the replay and it did, so I was happy about that since replays are very important to me. In the past, however, I haven't been so lucky. Sometimes I get error messages or it just won't load. I can't remember the error messages, but I think some of them said something like "Package not available."
Are you doing this with the Imola cars, because 1. The workshop does not contain the Nurb track update 2. The cars are no longer the same build (vec wise) If 1 or 2 then yes, you wont be able to watch that replay anymore unless you have the old cars and track installed. To save space, i am not keeping all the tracks and older cars in workshop. So this was not due to any update - but sure it should just refuse to load it.
I was trying to to load last month's VEC at Nurburgring and it worked. I have the cars installed. But I had to try 3 times since the first two times it didn't load correctly. First time it showed text where the replay should've been and the second time it loaded with the wrong car. In the main menu for single player, I had to choose the correct car for the replay to load correctly with the correct cars. Also, don't having replays that rely so heavily on the package to be installed sort of make the replay useless? If you reinstall for any reason, those replays are gone, unless you keep the packages. It almost makes replays useless/pointless, doesn't it?
The replays are there. The program filters the replays of the installed content. With the packages is easy, but the problem comes with the workshop content, where you can't control the updates.
I can imagine a "replay packaging system" that saved the content used along with the replay and then unpacked it into a temporary rFactor install to replay it. I don't think it would be difficult to do but I'm not convinced it would be used very much.