Problem with Surface Morph

Hello,

I feel like i have to preface this by apologising for how inept I am with Grasshopper. I'm sorry.

I'm trying to morph a rectangle with two triangles cut out of it onto the webs of a loft formed between two voronoi structures. I'm trying to use Surface Morph, but to no avail. When i've used Surface Morph before i haven't had to enter a value for 'W' and it has still worked. I'm instructed i have to enter a domain here now though, and when i do it starts saying the values for 'U' are invalid.

Please if anyone has any suggestions i would be very grateful for your advice.

Thank you.