How do I move the whole Grid
To move the whole grid you need to select the Move Grids tool, to get this you ^ (control key) click on the Grid Selection tool, see example below.
How do I get the Scale to look correct
Looking at the example image below, you first need to know approximately how high and wide in 'reality' is the area you can see of the back wall.
Let's say that the height is around 170 cm and the width is around 200 cm. So with the Grid Layer selected go to the Grid menu and Scale, then set as below.
In this case, it is the Total Width and Height we are concerned about. If your grid is significantly larger than than the area, then you will need to increase the sizes a little in the Scale window to allow for this.
Quality of the transferred file is not good enough
What can you do to get better quality in the transferred design?
Here are a few tips to help you get the best results
1. Make sure the spot layers in the design/source file are 8 bit, then 'Transfer High' instead of Draft. This will anti alias edges and instead of finer lines disappearing or breaking up they will become paler.
2. Increase the resolution if the scene using Edit > Resize, for example if you scene is 300 dpi, try making it 600 dpi, then re-transfer and you will see far better detail in the transferred design (increased the resolution of the design/source file will have little or no effect).
3. If you are gridding a room to show wallpaper on, ensure that the vertical grid lines are precisely vertical by using Guides for the Grid to snap to. This will mean there is less distortion in the transfer which can be particularly noticeable if your design has strips in.