In the Time and Dialog functions is a VI called Wait (ms). This VI waits the set number of ms before continuing. You may want to put it inside a single frame sequence to force data flow. (i.e. you have an error output from the previous function that you wire to the single frame sequence with the wait inside and then wire it out again to your next VI. This will force the "correct" execution order.)
If you are using Windoze, then you should be aware that there will be a certain variability in the timing due to Windoze multi-tasking (or at least what they call multi-tasking).
Rob
