I have download the 17 october 2006 nightly build.
Other->Bulid field is lock? How to open this?
You don't have to. When you open a single-file C::B operates (compiles) in single-file mode automatically. When you create a project you can choose whether this shall use a Makefile or the C::B build system. This option is a bit confusing, though... ;-)
How to add some header to cache?
I hope you mean the CC cache - this isn't clear to me. If so: After RC2 the cache has been disabled because it 1.) caused issues with corrupted cache files and 2.) didnt really speed things up (after the CC revamp the cache was obsolete). So as it is written in the settings: This will be removed, sooner or later.
If you still have cache files you can safely remove them - they on't be used anymore.
With regards, Morten.
Ps.: Yiannis (if you read this): Maybe the time has come...?! ;-)