Lapeyre - Petits Carreaux

[Alane]

Has anyone any experience of fitting these to the Lapeyre Tradition Chene range? We have bought two windows with the Oscillo-battant facillity (tilts and opens) together with the Petits Carreaux - the fake small windows that attach by hinges to allow the glass to be cleaned. A bit questionable in terms of authenticity I know but only way I could see to get double glazed windows for an old property.

The Petits Carreaux frame appears to be about .5cm too narrow, height is ok,  to engage with the clip to secure it to the window surface. I'm wondering whether the Oscillo-battant windows aren't a standard size or whether I've done something wrong. Unfortunately I only tried to fit them yesterday (Sunday) morning and had to come back to the UK yesterday evening and I'm not sure if my French is up to a phone call to discuss this with the depot and I shan't be back for a couple of weeks. I'd appreciate information from anyone who has fitted these units.

Best Regards

Alan.