I have a work item with range and start attributes, start is the first frame in range. I then use a 'work item expand' to create a work item for each frame in the range array. This works fine but if I try to set the work item frame I get a warning message: No work item to use when evaluating PDG attribute access in 'topnet/workitemexpand1/framestartx' I have 'Frame Start' set to @start. Can the parameter expression not read attributes from the upstream work items or am I missing something?
That's actually an issue with the Work Item Expand node -- it only evaluates the Frame Start parameter once, and assumes it's the same for all work items. I've fixed the node so that it evaluates the Start/Step parm for each input work item instead. Those changes are available in the next daily build (H18.5.581), and will make the node work the way you expect.