Page 4 in the CIC Web Applications ICG:
3. Enable server as proxy and enable response buffering:
a. In IIS Manager, click your server.
b. Double-click the Application Request Routing Cache module.
c. In the Actions pane, click Server Proxy Settings.
d. Check Enable proxy.
e. Change the Response buffer threshold (KB) setting under "Buffer Setting" to 0.
f. Click Apply