Query on Vango Kela internal “bedroom”

[SailSki]

Hi all, slightly off topic from Calis, but was too busy in work to get hold of Vango during the week to check....
Does anyone know if the internal bedroom which came with Kela II (uses toggles into loops in the awning) is compatible with a Kela IV (which seems to have a “rail” without any loops).
Unfortunately our Kela II is in UK and the IV is half a continent away at the moment, so difficult for me to check directly
Thanks