Home Studio Instrument Definition

I've been using Home Studio 2002 happily for a few years now, but recently bought a new pc running Vista 32 bit and a Yamaha Motif ES Rack sound generator. I found a .ins file on the net for the Yamaha and used the instrument def pulldown in Cakewalk so I could get easy selection of banks and patches. So far, so good, that works fine; the right instruments are selected. The problem is, even with the "save settings" box checked, it won't! In other words, I have to do the Define Instrument routine every time I open Home Studio. Anyone come across this before? I really need some help with this.

Thanks for the tip! I got around it in the end, I think. Cakewalk stores all of its instrument def files lumped into one "Master.ins" file so I just cheated and substituted my Yamaha ins file under the same name and it seems to be working now. I'm still none the wiser as to why it didn't work the "proper" way, though. Oh well...