resizing horizontal or vertical lines bug

i'm on xara xtreme 0.7 (1763)

has anyone else been getting a bug where the width, height and y coordinate of a vertical or horizontal lines are way off?

what i'm selecting at the moment says 1332 by 327636.3 pixels, and x:-768, y:-164564.3 where in fact it's nothing like that -- about 150 by 0 pixels and at a positive x and y. this persists even after restarting xara or copying and pasting to a new document. i can move them around without a problem by dragging but changing any value in the object properties panel or trying to scale the objects by any method produces unexpected results -- either the object disappears (presumably ending up far off the canvas) or just moves somewhere other than what you typed.

i can reliably reproduce this problem -- just draw a horizontal or vertical line and change to the selector tool.

the same problem appears when selecting a group containing such an object or multiple objects when one or more of whom is such an object.

i haven't been able to find any way around it and for the drawing i'm working on at the moment it's a real problem. i don't want to convert lines to shapes and forfeit the ability to change thickness etc later when all i want to do now is scale it along with its neighbouring objects...

edit: it may be something to do with the "scale line widths" button actually -- if i switch that on everything seems to work. but i might not want that on...