God knows how you managed to miss one of the darkest parts of sim racing history. When Sierra was taken over the Papyrus dev team were made redundant. DK then bought the code (but not rights) for N2003 and formed First Racing with some of the Papy dev team as well as some of Project Wildfire (T/A, GNS, CTS mods). They had a beta sign up but very little was heard.
In the mean time Redline were still working on there GTP mod (which had been in development a long time). Then when they released it First complained that it was a breach of the EULA. This soon led to First being known as Fir$t and an altogether not too pleased sim community. After a couple of weeks First allowed Redline to re-release without the skins and tracks so that the mod breached no copyright.
Then DK later issued a statement saying that all mods using a modified exe (plenty in development including JGTC, Funny cars, historic Le Mans, sprint cars, Indy cars etc.) were ilegal and would face a legal challenge from First. At this point most gave in but not TMC McArther who refused to remove his mods, this led to a court case which resulted in both sides claiming victory.
First then came back with iRacing more recently, little is know except what is on the site and that it is likely to be based on the N2003 engine and (controversially) could be a subscription service.
too bad rscnet is down so i cant refresh my memory