XP reward after event
It sounds like you might be the victim of DR. After doing the same event so many times it starts rewarding less and less experience and karma and gold.
However, if this is the first time you have done the event it is more of a bug than anything and should be in the bug sub-forums, not technical support. Technical support is more along the lines of hardware issues.
Primary Guild: Testing Eternity [TE]
Chloe (Version 3):
[i7 930 @ 4.1Ghz (1.3875V) w/Cooler Master 120M][Gigabyte G1 Gaming GTX 970 (stock)]
Chloe (Version 3):
[i7 930 @ 4.1Ghz (1.3875V) w/Cooler Master 120M][Gigabyte G1 Gaming GTX 970 (stock)]