I do. After I was diagnosed with GP, but Before I was diagnosed with my food allergies and mast cell disease, and subsequently placed in TPN, I relied on Boost and Ensure drinks most days, especially when in WDW because of all of the walking. Can you tolerate anything like that to help make sure you get the calories and nutrition you need for a vacation like Disneyworld? That was always a lifesaver for me because I could not consume enough food to maintain adequate nutrition status. I also in general relied on a lot of smoothies and soups.
As far as fresh fruits and veggies, I have oral allergy syndromre and mast cell disease so I cannot have any raw fruits and vegetables and only a select few if they are cooked....a lot more than usual. The chefs the past few trips were very accommodating about that. And when they brought it out, they always asked if it was cooked enough...if it wasn't, they would cook it until it was safe for me to eat.
I would definitely recommend asking for a chef because they might have some ideas that you might not have thought of. They might not know what gastroparesis is, and as you probably know, everyone has different severity, restrictions, etc, so I would request a chef and not necessarily tell them you have gastroparesis since they might not know what that means, but I would just be specific in what you can and cannot eat and see what they can accommodate for you.