Are they on the habitation door or the windows? (or indeed both) Are they pleated?. I am sure if you come back with an answer someone else will have encountered the problem, and may well have an answer. I only know that door frames are hidden fixings, and windows are of the spring ratchet type of fixing. Difficult thing to do I would imagine.
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.