Hi @acacil,
Here is a model that shows a way to set up the number of pallets and and pallet columns. It uses a group of the single initial floor storage object, and then parameters to control the number of floor storages created, as well as the number of levels (pallet columns) and even a way to increase the width of the floor storage if desired. 
This first picture is the parameter for the number of Storages to be created. Some key information is that the reference here should be the group that holds the initial floor storage. Within the On Set code you can change the X-step which sets the distance between the created storage objects.

This parameter sets the number of levels (pallet columns). You can easily change the upper bound to create a higher or lower max number of levels. The custom code used is shown in the image below. This is the same code that fires when you manually change the storage object dimensions through the properties of the storage object. The reference must be pointing to the initial storage object within the group. That means that whenever the model is reset, all storage objects that reference off of the initial one also will be updated to have the same dimension.


This last image is the NumBays parameter. The setup is the same as the NumLevels parameter, however the custom code is slightly different.
Some notes. If you will use this in conjunction with the other model I shared, you will need to set the initial storage object to its max dimensions and set the labels for each row prior to running the model. This will ensure that the correct labels are all set no matter the size of storage object you set within different scenarios.