I have used several versions of DraftSight and on both Linux and Windows and always have the same issue.  Initially all user input works well but after about ten minutes of use, the user input becomes very sluggish.   The pointer can't keep up with mouse input, forcing the user to have to wait.  This sluggish behavior will last for several minutes and then normal operation resumes.  Then after a few minutes of normal operation the user input becomes sluggish again.  Since I've seen this behavior occur on different PCs and with different OSes, it can't be a hardware related issue.  It becomes very aggravating to cope with and hope to find a solution, event if it means purchasing the product assuming the cost is reasonable for an amateur user.  I really like the product aside from this really annoying problem.

Often times it is just easiest to restart DraftSight about every five minute which makes it very impractical to use.  Any help would be greatly appreciated. 

Given this ongoing issue/bug/spyware,  I can't recommend the commercial version to clients as an alternative to you know who's, although I would like to.  Given this issue, it makes me wonder what  the software is doing during these cyclical sluggish periods when it can not keep up with user input?