Thanks to everyone for their advice.
moffdnb: found that folder, it already has my layout .pgl file in it. Like I said, I can manually apply the layout. Do you mean I should save another file here?
Zo: I have separate template folders for X1 and X2. When I save a new template in X2, it's definitely going into the X2 folder. Tried running the plug-in manager outside Sonar, didn't make a different
Swamptooth: funny thing is that it works for my FX layout, but not for the instruments one.
frakjcc: my template already has a track.
Bristol_Jonesy: good point - done it though. When I open the template by double clicking it, the new layout is selected
I think I'll try starting from another template - perhaps there's something wrong with my normal.cwt. I'll post if this makes a difference. As moffdnb and scook have got it working properly, it looks like it's a problem on my system
Simon