Memory hog

I am having trouble with EndNote X2 on my Mac PowerBook (G4@1.3MHz) running 10.5.6 with 2GB RAM. I have one library (single file) with around 600 entries (half in trash which will be emptied in due course), and about a dozen groups. After adding a few entries, opening a few more entries and adding a few links to pdfs I find the memory consumed (both real and virtual) explodes: virtual goes to around 3GB (from an initial 900MB thereabouts). Lots of time spent paging in and out, especially when I switch to another app, which I have to do all the time as I am adding linked pdfs. Looks to me like a memory flood (not leak). Any ideas about what is happening?

Also, I use You Desktops and have EndNote on one window and other apps on other windows. If I switch to another window (often) I get a generic service error, actually I get it 30-40 times and end up force quitting EndNote. Any ideas what is going on here?