Since the first value of the GetShapeshiftFormInfo is the texture, you should use
instead of
Lua Code:
local texture = GetSpellTexture(icon);
And about the scroll frame, since the shapeshift form count is little, there is no need to use a scroll frame to contains all them.
If you really need, you should create a frame as the scrollframe's child
Lua Code:
local scrollFrame = CreateFrame("ScrollFrame")
local container = CreateFrame("Frame", nil, scrollFrame)
scrollFrame:SetScrollChild(container)
And then create all list items on the container. Scroll childs in the scroll frame is just moving the container, you can set its location by yourself or just use method:
Lua Code:
scrollFrame:SetVerticalScroll(value)