Could be something weird in the constraint method settings in the work environment or possibly the grid.
Sometimes it's just a continuation of having one 'bad' element in the drawing and shift picking up on its slight rotation. Maybe something in your template is slightly off axis, if you've been having the problems over many versions and projects.
Frustratingly it is ussually a case of PEBKAC
Are you allways showing the tracker and the angle of whatever you are drafting? I have set up my working units with one decimal accuracy to show in tracker, to pick up on these kind of frustratingly small offsets.
I'm very obsessed with making sure everything I draft is accurate. Slight rotations, decimal 'shifts' in elements... The frustration of fixing it... argh!
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
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