Archicad 26 glitching, lagging when selecting 'simple' wall (single skin, no composite)

[Aquavit]

 

Not sure if this is the right place for bugs but am struggling with AC26 slowing when I select a 'simple' wall (ie single skin non-composite wall).

When such a wall is selected or the wall tool is set to a simple wall (2), of any building material, when I move the mouse, zoom or pan, the icon in the tool bar button for selecting the building material (1) flickers and there is a significant lag in selection or any editing process (3). (numbers relate to attached screen grab)
 Any thoughts greatly recieved. 
thanks

[Karl Ottenstein]

The jaggies (stair-stepping pixels) in your screenshot indicate that you do not have 2D antialiasing turned on within your Work Environment.  Or... your machine is set up to use a basic on-board graphics card (Intel) vs a dedicated graphics card.  Please update your signature so that we know what you're actually using (it shows AC 23 vs 26 in your question... so perhaps your computer is different now as well).

Check your Work Environment and report back if you settings selected similar to these - in particular 2D antialiasing checked, and 2D hardware acceleration on full...

 

[Aquavit]

Karl good morning, thanks for the steer on attaching images and out of date signature, updated accordingly. 

Very appreciative of your keen eye, I didnt realy notice the 'jaggies,' have switched my 2d antialiasing is on - now i really notice them when I toggle! 

My original problem endures, to recap: simple walls, whether just with wall tool activated or actually selecting a wall, causes the 'structure-dialogue' in my tool bar to flicker and all editing processes to lag enormously, especially when picking up and injecting parameters, freezes for 5+ seconds (even ESC to return to Arrow Tool unresponsive).

I have tried a number of things
1.-Purged a sample model of all unused attributes at once, nothing changed. Saved, closed and opened the file again and the problem appears to have gone. NOticed an older version o fthe same file doesnt have the problem.
2.-I then purged each set of attributes individually on another model with the same issue, saved and reopened it - no joy still there. \
3.-Finally i discovered when I hide the 'Structure' dialogue on my tool bar it no longer does it! 

Thoughts... thanks