I would like to see a video of your results.
I made a video showing Rush 2049, check it out. Car oscillation is zero.
Another detail I forgot to mention is that I use high quality Cat8 ethernet cables. I believe that any help, however small, is welcome to make this game work correctly.
NOTE: I didn't mean to be rude. If I left that impression, please forgive me.
No worries at all. I figured it was a misunderstanding. I am so happy you found out how to do this and get these working as Rush the Rock is my favorite racing game.
I did some more testing and ever since I added the wintun checkbox (and possibly doing the correct order but I think it was the wintun), I get pretty much zero oscillations of cars for two players. When I have three racers join a race, I get just the smallest amount of oscillations. When I do a four player race, I get just a little more but not enough to worry about. Before the wintun checkbox, I would get cpu cars sometimes going underneath the road and then sometimes flying in the clouds when they should be on the road. That has not been seen since adding it.
The only issue I have found is when doing four player races, it sometimes starts the race with a random racer or two being against 7 other cpu cars and the other two or three being in the race together. It appears to be a timing thing on when the countdown happens to go to 0 and people accept their car and auto vs shifter. It happens maybe every third race in 4 player but it has never happened to me in a 2 player race. A 3 player I think it happened once. I will have to get some friends over to test to see if there is a trick to get around it in 4 player mode or if I just have to randomly restart and try again.
FYI I was able to automate adding the Ethernet connection to the bridge before starting Rush the Rock/Rush 2049/California Speed and then have it automate removing it from the bridge so all other games work. It works really well. I will post the code when I get a chance. I personally have it for BigBox (Launchbox) but you could probably update it just slightly for any front end. This code is for windows 10 since supposedly Microsoft added the Netsh bridge commands to win 11 (assuming on one of latest patches that has it) so having win 11 makes it easy. On win 10 it was a pain but now that we have the code it’s fairly easy.
Are you running Windows 11 or 10? I noticed on my laptop that is win 11 that installing that tap and openvpn version created the extra network offload adapter that you had but on my win 10’s it did not.