Sigh... First test before committing. InvalWindowRect and friends are window object methods. Fixed.
diff --git a/Mac/Lib/test/tscrollwin.py b/Mac/Lib/test/tscrollwin.py
index d91f6b9..661ad2b 100644
--- a/Mac/Lib/test/tscrollwin.py
+++ b/Mac/Lib/test/tscrollwin.py
@@ -47,7 +47,7 @@
 				self.vy = value
 			else:
 				self.vy = self.vy + delta
-		Win.InvalWindowRect(self.ourrect)
+		self.wid.InvalWindowRect(self.ourrect)
 
 	def do_update(self, wid, event):
 		Qd.EraseRect(self.ourrect)