Saddle for Daisy

When we bought Daisy we got her bridle and bit with her, and borrowed a saddle. We ordered a 2nd hand saddle from the UK (they are quite expensive here- and rideaways charge very reasonable postage). It arrived last week. When we first tried it on Daisy she was not a happy camper. We went through the process as described on the internet, putting the saddle on her back without a blanket underneath and inspecting it from all angles to make sure it wasn't pressing anywhere on her spine before mounting. When Doug mounted she put her ears back and bared her teeth in an unusually angry fashion. Doug got off and I started to get on at which point she snapped at me - which is unheard as she is quite mellow normally. I didn't continue getting on, we went back to the borrowed saddle and she was fine, then back to the new saddle and angry Daisy was back. We stopped at this point for a reevaluation.
It seems hard to find saddle fitters here, but a friend of a friend allegedly has details for one. As the friend is bringing her horse here for a little holiday next week, we were waiting until then as she wants a saddle fitter to look at her saddle too.
However the owner of the borrowed saddle suddenly needs it back. What were we going to do?? After extensive searching in the Yellow Pages and phoning various local equestrian shops (in French yes) to try to locate a saddle fitter, I phoned the nice people at rideaways. They were very helpful and said we needed to put the saddle back on Daisy and sit on it, so we could tell them some measurements (distance from pommel to withers initially). We weren't super keen to repeat the crazy fang Daisy experience, but Doug very bravely volunteered (ok I told him it was his job) to mount while I did the measuring and held Daisy's head pinned so she couldn't chomp him.
But as it turned out we put it on her back and she was fine, not a bother with it at all. Doug then went for a little ride (as recommended to settle the saddle in position before taking the measurements). Daisy was fine with ears flopping happily. So we are not sure what happened the first time, but we are glad it seems fine now. The saddle fitter will be coming anyway so we will get him to look at it just to be sure, but all seems good.
We are very relieved as the saddle is nice and comfy for the rider - plus we were going to have an issue having given back the loan one and not yet got this one right.