Dave,
Thank You for providing the detailed evidence based explanation. I was going mad!
I will change the precision to 0.000000
And locate the plug in that allows for coordinate tracking like your screenshots.
I'm done for the day, but will start fresh tomorrow with purpose!
You have literally just made my day,night,week & month. Thank You.
Nothing like a glitch to bring one back down to earth. lol
@dave r said:
Could you share the SKP file? It would be easier to help you if I could take a look at it.
Hi Dave,
I have replied with a 500kb .skp file attached twice, neither post has been uploaded. It's been about 4 hours since posting. Not sure if i am doing anything wrong with the post?
Lights1
Thanks for the replies, I hope 17 mB .skp file is ok?
I reverted all my geometry back to layer0 using the plug in mentioned above. But i have opened earlier models and they are all behaving like this.
Sometimes the rectangle cuts the face, sometimes it does not. Even if i hold the inference til it actually says "on face"
I am at an end, i don't know how i am going to be able to continue unless i can sort this out, or I will have to spin a story to the missus that windows are not allowed due to council by laws or something... 
Could it be an alignment issue to the axis?
I have seen diagonal faces in the past, and had walls not square, but this issue really seems like something else.
I have deleted everything else in the model to get it under 5mb.
I don't know how that is happening, as i am completing all of those rectangles in succession, in the same selection context, in the same plane view. one after the other, some are thick, some a thin.
I have tried on other walls in my existing model and the same thing happens.
However, i just drew a new cube, and had no issues on the new cube. It is something happening to my pre existing shapes. I am confident all walls are parallel.
I have been using sketchup for about a month, only tonight have i ran into this issue...
I am attempting to push/pull a hole in a wall for a window, but the rectangle i draw on the wall surface is coming up with "thick" lines and not drawn on the surface.
If i do the same action ten times over, i might get 2 or 3 thin, pushable rectangles and 8 thick ones that are not making new faces?
When typing in the dimension the lines are thick every time, when lining up with guides the lines are thick every time.
I have not noticed this issue prior to tonight.
If you take a look at screenshot you will see the difference in line thicknesses... Any help would be much appreciated because i have hit a brick wall with this now...
Troubleshooting:
I have toggled hardware acceleration on/off for now improvement.
I have stopped a plug in i installed TIG layerwatcher , again did not help once i stopped and reopened SU.
