You can right-click the border of the cluster and choose "Reorder controls in cluster..." The user interface isn't as intuitive as it could be, but it will let you rearrange the items. If you are using the cluster in several locations, you should make the cluster into a type definition, and replace all existing uses of that cluster with the type definition so that they will all match. They will also update automatically when you make changes to the type definition. Otherwise you might have a situation where you have several clusters with identical data types but with elements in a different order, and your data will get relabeled when you wire the clusters together. The data will be in the same order, but since the element labels are in a different order, you may not get the data you want when you unbundle by name.
