Hello I have an old paper survey, so am doing some old school map drawing over a scanned background sketch. My first for a few years. I have noticed that XTherion seems to not be able to display the background sketch once you have used the mouse wheel to zoom. The sketch just vanishes, even though everything looks OK. Using the magic of version control I can see that the only significant change that XTherion makes to the dataset is that the ##XTHERION## variable is no longer one of the present values. ie 100 has changed to 62 in response to the mouse wheel zoom. There are no problems if I use xvi file sketches as generated from PocketTopo, so it is just a bitmap thing I suppose. If I manually change the value above back to 100, the image displays just fine. The + - zoom button on the interface work just fine as well. I am using 5.4.1 - 88c8a06 Mouse wheel zoom is a nice feature, so it would be worth finding a fix for this. Bruce
