just to clarify for you...."flash counter" is a counter that increases each time you flash a rom or whatever. the know 0x1 is a flag which doesn't continually increase, it will either be 0x0 meaning that it's a stock/official system, or it will be 0x1 meaning that the knox flag has been tripped because some part of the system has been modified (e.g. flashing custom rom or recovery, or rooting etc).
so if you want a totally official/full warranty guarantee, don't modify the device in anyway. if you've gone past your warranty date or just don't care about it then you can root/install custom roms kernels and recoveries, but this will likely trip the knox flag if you have the kitkat bootloader.