I am new here, but not new to computers or coding, (developer in rl) , but in the case of physx issues etc, usually I notice two things.
1. followup installtion gets corrupted. Unless your very very savey with regedit and know how to disable, re-enable values and what to look for, the only solution is a full re-install of the OS and everything else.
2. Physx along with other third party development software is usually out of the hands of the actual development team using it. In many cases, I have found my team reverting back to previous builds prior to release or re-inventing the wheel so to speak. When and if when, a small amount of our user base experiance issues, we attempt to fix those issues. In some cases, when those issues are beyond our control (old hardware, out of date drives on the users computer) we weigh the pro's and con's of what to do. Some development houses decide to bring up the issue and wait for the third party developer to find a fix, release an older compatible version of the application or finally offer an appology and offer refunds, stating that as technology moves ahead so does the software. We can offer you an older version or a refund.
Now I am not with this company, but that's my experiance. While I know it's not the best news to hear, #1 is usually a solution to most of I would say 96% of the issues and only a few very few can't fix it for hardware or software out of production products that reside on their systems. Again in those cases we refer to rule 2 and give that advice and when that fails we offer the final alternative to a refund. It's rare , but it does happen.
I have read a few threads about those that have been having issues, thou I have yet to see anyone state that they did a full-system format and re-install. While this option is a horrible option, fact remains that systems after a point need such a flush to fix many issues. I can not even count how many times back in the day when I started as tech support and told clients that they had to reformat and that was the only option. One client had so much email storage that it would boggle the mind. But along with that he had 57 constantly running applications and more. Then wondered why his system was slow. Others haven't redone their system sense they bought them. The general rule of thumb out there is , every 2 - 4 years your looking a whipe and re-install, depending on usage on a particluar system. That is why people as myself, always recommend a second drive to install games, applications and the like on. While in the end you would need to reinstall those applications, you would have the core of the original handy to get save files and updates taken care of.
Finally to make sure you save all your bookmarks in a bookmark file, and dump your full documents folder into that drive. Then you basicly have everything you ever did in one location with all your stuff right there ready to be put back in place after a clean install.
Anyways, sorry for the rant there :) Just trying to help, those are my suggestions and you can take them or leave them, but alas I am just trying to help.
A Fellow Train enthusist,
ps. btw, phyx drivers can have issue with overclocking cores and video cards. If you are overclocking , try it without doing so, this means disable in bios, turn off all active overclocking software using mscofig etc. Depending on you system bios core etc, all can be looked up on the web for compatiblity issues. And no, sadly you shouldn't have to go threw this trouble to get a game to work, but trust me, your not the only one and this is definitly not the only game where things like this happen. GL!