All of a sudden, right in the middle of chapter 2 roche path, i suddenly and for no obvious or apparent reason, lost the ability of talking to ANY character. I can still use items and storage, but the cursor for initiating dialogue is gone for good.

I cannot talk to anyone. And i do not know why. I searched before posting, and found out that AMD cards and their updates cause this. I have ATI myself though, so i do not believe it is the same case and the same methods for solving it can produce results.

Please help me, i would hate having to permanently abandon witcher 2 before even i get to finish it even once. Although it has been a terrible bugfest so far, it deserves at least one playthrough. Especially all those crahses to desktop made me hate it, but still...

AMD = Ati (has been for a few years, as AMD bought Ati back in 2006)

So maybe the solutions you found might work.