Sorry for my English.
At snmp-mastering link in label display correct rx, tx speed, but in history… 
This image illustrate problem.
(I export configuration from Dude3b3 and import to Dude3b4).
ditto here, problem appeared after upgrading from beta2. Even tried recreating the links, and still the graphs get hosed.
Just verified the bug on a brand new dude 3.0b4 install, with fresh dataset.
to reproduce the bug:
create a link from one SNMP device to another, set mastering to SNMP, pick an interface, let it sit for a minute… Go back, look at graph.
P.S.
We really like this feature. We hope it gets fixed some time soon. 
I’ve noticed that the bitrate is measured over about 3hours period. Is this a setting that can be changed, if so than how can we modify it.
Actually it would be great if it is configurable.
But for the time being, we hope it returns to the way it was before.
Related to this:
Some links still doesn’t show the graph when you hover the mouse over it.
Some links doesn’t either show the rate in numbers in the link’s RX/TX box.
All wil show the bit rate if I disabled&re-enable the graph bit rate in the link settings.
same here .. i have remake the link but same shing .. dude is not drawing corect the graphs
Same here, like said, it shows the real-time stats on the link itself, but not on the charts… even when you export to PNG, it graphs the same. But on specific items, it works perfectly. It seems like a “on or off” type of chart deal. No good. Please fix MikroTik!! GOOD FUNCTIONALITY!!!
Just my two cents. Love the graph, but 3b4 is not displaying history correctly.
problem solved .. return to version 2.2
Problem solved in 3b5, thanks.
Yup. Working great!
Thanks guys.