initialize Height in SetUp() to fix cell height problem when creating new tables (grids)

PROMS/Volian.Controls.Library/StepRTB.cs

@@ -316,6 +316,7 @@ namespace Volian.Controls.Library
 
 		private void SetUp()
 		{
+			this.Height = 10; // initialize the height to 10, the default height was too big for the cells in grid tables
 			BorderStyle = System.Windows.Forms.BorderStyle.None;
 			this.ScrollBars = RichTextBoxScrollBars.None;
 			this.DetectUrls = true;