Hi Naresh,We use firewallanalyzer @ fwanalyzer.com to monitor the pix , take a look at demo.fwanalyzer.com.

The router's sysUptime resets after a specific time(It couldn't hold more than that!!) during which you will get such flows.

Hi,I use NetFlow Analyzer at netflowanalyzer.com , It's the best so far. Good bang for the buck.It does have a free edition.

Hi,Seems you have not enabled netflow on all interfaces.Enable netflow on all interfaces to see both IN and OUT traffic of all the interfaces.

Hi,I have the same problem. Can't believe how this is possible.