Just tried your new beta library (API Performance Improvement) and the pipe performance boost is indeed pretty significant.
However I seem to have a problem with firmware 1.5 (fast wire/trigger updates) on XEMV1 FrontPanel 1.2.5 when running the ReadFromPipeOut function. The ep_read signal doesn’t seem to be asserted.
I first experienced it in my app which used to work, but not anymore after upgrading my XEM.
With the PipeTest utility, the PipeIn counter is updated but not the PipeOut one. However, with firmware 1.4, everything is fine.