Can I mix and match with WinCVS or the command line?
Yes, you can check out a module with WinCVS and use it in TortoiseCVS or vice versa. If you’ve installed CVSNT as command line client you can also mix with that. Some CVS clients work incorrectly with daylight saving time or time zones in general under Windows. You should use CVSNT or a sufficiently recent version of WinCVS with TortoiseCVS version 1.4+, especially on NTFS file systems.