(1) Insert a cell
To insert a grid cell next to an existing cell, select two grid nodes of the existing cell (RMC on a node, hold the Shift key then LMC on the second node, the segment will be highlighted) then RMC to display options, select Line Mirror option as shown in Merge Two Grids#Figure 1. As a result, a cell will be added that shares a grid line with the existing cell as shown in Merge Two Grids#Figure 2.
Figure 1 Define where to insert a cell.
Figure 2 A cell is added to the grid.
(2) Insert multiple cells
The method to insert multiple cells is similar to inserting a cell, the difference is in the selected grid line. In this case, we select a longer grid line that contains many cell sides in the same line by LMC on the first nodes then hold Shift and LMC on the second nodes (Merge Two Grids#Figure 3), then RMC to display options, and then select the Line Mirror option. As a result, a number of cells will be added as shown in Merge Two Grids#Figure 4.
Figure 3 Define where to insert multiple cells.
Figure 4 Multiple cells are added to the grid.