I am having a fluky problem in System 7.0 and 7.01 on my Mac IIsi. When mousing around on the esktop, moving icons, etc., the "up-click" signal from the mouse is missed by the mahine (orfirmware/software). I have heard that Sys 7 handles the up-click signal differently than sys 6; has anyone heard of this as a bug or experienced a similar problem.