Total bandwidth through the system is now shown on screen 6 along with current bandwidth on all interfaces. It is also shown if you run the "netmon" command from the console or through an SSH session. However to answer your question about ipfm. I suspect that this is one of the packages that would require rewriting the source code due to the kernel change. This is because the numbers were changed from 32 bit numbers to 64 bit numbers so the system could count traffic into the Exibyte range. Which on a rough scale would be a 100Mb network card at full duplex running maximum traffic 24/7 for about a year.
If you are afraid that you might make a mistake. The chances are high that you will never learn anything.