Hi i have recently upgraded to fme 2015.1 and a workbench i use is giving me a differnt output to when it is run in 2014.1.  The workbench basicaly dissolves thousands of polygon in to a clean version, only in 2015 it misses quite a few out.  I've tracked the problem down to the dissolver but how is it different to 2014 and what do i need to do to my data to make it work the same?