diff --git a/PROMS/Volian.Controls.Library/StepTabRibbon.cs b/PROMS/Volian.Controls.Library/StepTabRibbon.cs
index de006f43..eba3ba3d 100644
--- a/PROMS/Volian.Controls.Library/StepTabRibbon.cs
+++ b/PROMS/Volian.Controls.Library/StepTabRibbon.cs
@@ -709,6 +709,9 @@ namespace Volian.Controls.Library
 
 		void MyFlexGrid_SelChange(object sender, EventArgs e)
 		{
+			//B2017-156 Don't allow alignment or borders if the selection is not valid
+			// Alternatively allow alignment or borders if the selection is valid
+			rbTblBorder.Enabled = btnTblDgnAlignText.Enabled = MyFlexGrid.Selection.IsValid;
 			if (MyFlexGrid == null)
 				return;
 			if (MyFlexGrid.Selection.c1 < 0 || MyFlexGrid.Selection.r1 < 0) 
@@ -1580,7 +1583,17 @@ namespace Volian.Controls.Library
 			if (!setting && MyItemInfo.IsStep && (eds == null || eds.Count == 0))	// this step is in enhanced, but not linked
 				allowDel = true;	// allow delete if not linked
 			btnCpyStp.Enabled = setting;
-			btnStepPaste.Enabled = setting;
+			//B20170-158 Allow a Unlinked Step to be pasted before or after a linked step.
+			StepTabPanel tmp = Parent as StepTabPanel;
+			if (tmp.MyDisplayTabControl.MyCopyStep != null)
+			{
+				if (!tmp.MyDisplayTabControl.MyCopyStep.IsEnhancedStep)
+				{
+					if (MyItemInfo.IsEnhancedStep) btnPasteReplace.Enabled = btnCMPasteReplace.Enabled = false;
+				}
+			}
+			else
+				btnStepPaste.Enabled = setting;
 			rbnCharacters.Enabled = rbnParagraph.Enabled = rbnLinks.Enabled = setting;
 			btnCMEdit.Enabled = setting;
 			btnDelStep.Enabled = setting;		// context menu item
@@ -1609,7 +1622,8 @@ namespace Volian.Controls.Library
 		{
 			btnPasteBefore.Enabled = btnCMPasteBefore.Enabled = enable;
 			btnPasteAfter.Enabled = btnCMPasteAfter.Enabled = enable;
-			btnPasteReplace.Enabled = btnCMPasteReplace.Enabled = enable;
+			//B20170-158 Don't allow a step to replace a linked step
+			btnPasteReplace.Enabled = btnCMPasteReplace.Enabled = enable && !MyItemInfo.IsEnhancedStep;
 		}
 		private void SetPasteButtonEnabled()
     {
@@ -3826,7 +3840,8 @@ namespace Volian.Controls.Library
 		{
 			bool enableContent = enable;
 			if (MyFlexGrid != null && MyFlexGrid.IsRoTable) enableContent = false;
-			btnTblDgnAlignText.Enabled = enable;
+			//B2017-156 Don't allow alignment or borders if the selection is not valid
+			rbTblBorder.Enabled = btnTblDgnAlignText.Enabled = MyFlexGrid.Selection.IsValid && enable;
 			btnTblDgnCopy.Enabled = enableContent;
 			btnTblDgnRemove.Enabled = enableContent;
 			btnCmGridInsert.Enabled = enableContent;