Officially, National Instruments doesn't support the use of Code Instruments on the GPIB-VXI/C any longer. I tried to find out what 0x87 means; however, I could not find any internal or external documentation for this status.
We have recommend using the VISA functions for more than 5 years. You would use viMoveOut and viMoveIn instead of the DMAMoveCI function. viMoveOut and viMoveIn both also use the same DMA logic as the DMA CI. They execute the move in a single shot. Furthermore, it provides better throughput because you don't have to do an SRQ to get the status byte.