We had three installed 2 weeks ago in a bay window. One of them is starting to pleat properly but the other 2 still bunch hopelessly (I suspect due to heat reasons - the pleater is the only one with a working radiator under it).
I didn't know about pleating problems before I had them installed, and the installer said it'd just take a few days for them to "settle". I looked it up and it didn't seem uncommon, so I've just been babysitting them into pleats every day. The bottom few folds are starting to behave themselves but still not the higher ones.
Still though, 2 weeks later and only marginal improvement. I contacted them today to ask how much longer I should expect this to go on for and the woman has said "since they are soft furnishings you may always need to straighten them" 
At no point was I told that! I have to stand on the window sill and stretch right up to straighten the top ones, it's hardly convenient.
Just wondering if anyone else has had them and whether they settled down, maybe in warmer weather (or if we ever get round to getting the sodding radiators fixed)?