Scintilla + VB probs

I just recently got rid of the RTB for my editor and replaced it with Scintilla. I am using a MDI. Placing multiple instances of scintilla on child forms is no problem but sizing them is. I create the scintilla boxes with CreateWindowEX and they suggest sizing them with the SetWindowPos api. Ive tried that but scintilla never seems to respond. I read the last param of SetWindowPos may need to point to some kind of struct to work with MDI properly (the tutorial was for c/c++). Does anyone know how to use SetWindowPos correctly in the MDI environment?

Heres the snippet im refering to:
http://www.scintilla.org/SciTry.vb