Ideally, get a copy of the ArchiCAD 8 Training Guide - it's pretty cheap.

Definitely NEVER use the visual values in the coordinate box while moving your mouse to determine length. As you note, it is at best an approximation based on the current working settings. No matter what your precision is set at, you will never get an exact length by watching these values.

Instead, get used to the R (radius) entry box. Pressing the R key jumps the focus there so you can type the required value. A typical "move" is to start a wall, and then shift-drag to constrain the direction, press R, type the length, and then enter to complete.

x, y, and a move the data entry focus to those boxes as well. Note that you can have relative or absolute coordinates (the triangle buttons). Any value can be locked by entering ALT-letter. So, alt-a would lock (constrain) the angle value to a specific angle while you next worry about the length (via R), for example.

As friendly as the AC interface looks, it isn't a piece of software that you can learn by exploring ... you really need to read the manual and/or have the friend who loaned it to you show you the basics. 😉

Don't be bashful about posting more questions here, though - but it would seem that the Installation / New User forum is where you might want to ask.

Have fun!
Karl

oreopoulos wrote:
Does anyone know if i can make the coordinate box higher precision than it does?

Preferences -> Working Dimensions.