Program BZ can generate a square array of 161 by 161 points, suitable for use with Excel. These can be read by Excel and used for making nice images.
Using Windows Explorer, locate a file representing a surface generated by program BZ. This should be in the folder where BZ was run, and will have a name such as "Diamond surface number 01.txt".
Open the file using Notepad. The file will consist of a 161 by 161 array of numbers. Copy everything (right-click on the Notepad window area, and click on "Select All", then right-click on the Notepad area, and click on "Copy") and paste it into an Excel spreadsheet. Select cell A1, right-click, and click on "Paste". At this point, all the data is in column A. To put all the data into their correct cells, click on Data =>Text to Columns (in Data Tools) => Finish (in the small window "Convert Text to Columns Wizard) If this has been done correctly, then row 1 and column A will start with the numbers 1, 2, 3, 4.
Select all the data in the spreadsheet. Easy ways to do this are: (A) Click on the cell to the right of the column header A. This cell is also above the row header 1. It's slightly grey and has a small triangle in it. (B) Press Control-A on the keyboard.
Click on "Insert" then click in the "Other Charts" and select the first of the "Surface" chart types. A small surface chart window will then open.
Right click on the edge of the chart window, select "Move Chart". In the "Move Chart" window, select "New Sheet" and click on "OK"
Right-click on the chart area, and select "3-D Rotation" To rotate the chart, use the up-and-down arrows next to the numbers with a degree symbol (°) next to "X" and "Y". The chart will update after a brief delay.
The colors might change as the chart is rotated. To prevent this, select "Axes" => "Axis Options" then change all "Auto" to "Fixed"
To remove all the straight lines and numbers, right-click on each one in turn, and click on delete. This is a bit tedious, so use the resulting chart as a template for future charts.
Save your work first. Then save the current chart as, e.g., template.xlsx. For all subsequent 3-D charts, open template.xlsx, and replace the data with new data.