Today I ventured to extend my learning by experimenting with mouse areas. Things that I learnt (eventually!) - 1. If you are working with a gauge with a transparent background (e.g. mine has a text string and a value with a transparent gap in between), the gauge mouse doesn't become active over the transparent area. I discovered this (eventually) by setting the main mouse area pointer to a hand, rather than normal, and spotting it only changed to a hand when over the text or number. Over the transparent area it remained as a pointer. 2. This also applies to "child" mouse areas, so if you define a mouse area that happens to be transparent, you'll never see the pointer change, and the area will never become active! 3. The FSX script interpreter is picky about spaces, so 0[Space](..... works, 0(........doesn't. Not easy to spot but you need to watch for it. 4. I never did get the tooltip to display what I wanted. Off to give the grey matter a break. Frank T.