I had to run chmod on configure before I was allowed to run it.
All right, it compiled and I now have libcapsimage.so.5.1.
Do I only need to install it it to /usr/local/lib for FS-UAE to "pick it up" ?
You'll have to excuse me but I'm still a bit new to Linux, but I'm getting there slowly.
It's actually a quite fun OS to learn using.