I have noticed this when using LV7 on a 800MHz machine with 256 meg of memory and the chart had a lot of data (also WinME). (I use this machine on week-ends to keep my code honest. If it can run on the old dog computer, it will run on new ones)
Try doing a "clear chart" as current as default before doing anything with the plot properties. I understand this as due to the fact that the plot properties will generally cause a re-draw of the chart. In my case this was slow because I was running in virtual memory. Just one idea, Ben <a href="http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=261&HRedirected=True&HUserId=101_3529&RFORMNUMBER=6";>Ben Rayner</a> <a href=" http://volt.ni.com/niwc/common.jsp?page=products_certification_cld&node=10638";> Certified LabVIEW Developer </a> www.DSAutomation.com
