Yesterday I added 3 cars in the store. Porsche Cup, BTCC Vauxhall, Mini Cooper. Paid and installed. However, when I went to select one of cars it didn't appear. Quiting rF2 and starting it up again seemed to fix it. I can't remember exactly now but I think the packages loaded when I restarted so probably they didn't install. Sorry I should have paid more attention but the last DLC I bought stuff in Steam and the one before that I think the in game store worked just fine and loaded the content I added. Actually, I remember it was even in the RC I tested it. One car or track I think.
I saw the same. I bought the new cars in the in-game store, I clicked "install now" and waited while they were installed one after the other (I think I saw the Vauxhall image but not the Porsche one, it displayed a small broken picture icon). When the installation ended I tried to select the cars and they didn't show up. They appeared after restarting the game.
If you install something while rFactor 2 is running, it can not appear, because the Game won't recognize it. So you have to restart rF2 or shut it down before you install something.
I think you misunderstand. If you install via the steam app while the game is running, sure, I wouldn't expect that to be visible until you restart. We're talking about the in-game store. It's very purpose is to install content while in the game. It used to work. Now it doesn't, at least for some of us. The in-game store was added earlier this year.
You are right, i wasn't aware, that Content, that was purchased in the in Game Store, was getting installed and available immediately, while the Game is still running.