I am thinking of shipping a box UPS Ground, with some necessities that I wouldn't feel like carting on the plane (while trying to deal w/two little ones).
I've done this. In my case I timed it so the package arrived mid stay. It was a special treat to celebrate a special day that was occurring during our stay. I'm willing to bet that if you addressed it as in the post above they'd hold it until you arrived.
I wouldn't send anything that you can't live without. Packages do sometimes get lost or delayed. Remember to pack it well, the last couple things I've gotten UPS really got worked over. They must have bigger gorillas working for them now.
I have shipped to OKW without a problem. It arrived the day before us. I called the front desk to be sure it had arrived. We had the rather large package delivered with our luggage.
Yes we have shipped a package UPS to OKW. We had it shipped 5-7 days prior to our arrival in case it was dropped off at the wrong location. You will need to ship it directly to your resort. On the box write down arrival date. We did this in three places. Then when addressing it write your name under the resort. As we checked in they had it in the computer that we had a package waiting. If upon check in you are not notified that you have a package then you will need to ask. Also if you use UPS you can track your package to see when it arrived.