I am running classic 6.7.2 in this location:

http://www.myserver.com/cgi-bin/ultimatebb.cgi

The only 2 folders on the domain name are:
http://www.myserver.com/ubb
http://www.myserver.com/cgi-bin
Nothing else. There are no other files on the domain name, which is used purely for the forums.

I want to set up threads on the same domain and play around with it for a while (maybe as long as a few weeks or a month) before importing.

Question:
Can I setup and put threads in the following location http://www.myserver.com/ (ie. not in any folder), without it affecting anything to do with classic? Is it safe to do that?

Thank you!

Yes; so long as you don't over-write any classic files there isn't anything to worry about...

Thanks. Thats what worrying me though - will they overwrite any classic files.

ie. does threads touch (in any way) those /ubb and /cgi-bin folders?

No, threads isn't a cgi script so it doesn't use the cgi-bin; and the ubb folder is a placeholder folder

OK so I'm totally safe then.
Thanks.