I think you may have a complaint about your dealer not being clear, but FWC’s ordering and change processes are made quite clear in the contract you sign when ordering. In addition, I don’t believe that, in their process, there is such a thing as “putting down a deposit to hold a spot.” You either place a complete order with deposit, or you don’t. If your dealer told you such a thing was possible, your issue is with them.
What may have actually occurred for you might have been what I did. I bought a camper that had already been ordered on speculation by the dealer. In such a case you’d think the dealer could agree to the sale without putting in a change order at that time. However, as I said in a previous post, I didn’t think to ask to do it that way because at the time I thought I knew what we wanted.