I think that the limit is 258 characters, which is a limit to the editor which is a third party editor called magma. Coping and pasting will sometimes crash QARun, which has been a problem for some time. It may deepend on the version of QARun that you are using. I have never had this problem that I can remember, but I remember seeing posts back as far as 4.7.2. I am now using 4.8.0 build 1484. I don't think that XP will make a difference other than the controls that you will not be able to test, such as the start menu.
[This message has been edited by chiefwiggum (edited 11-26-2002).]