I chose high priority, for this is an absolutely essential interface that 
should work completely.

After inserting a string into a cell text using insertString(aCursor, "some 
string", true) the inserted text is not selected by the cursor.

Example, oText is a *spreadsheet cell text*, which can be retrieved in the 
helper below.

Sub ManipulateText(oText as Variant)
	Dim clause1 as String, clause2 as String
	clause1 = "When Mr. Bilbo Baggins of Bag End announced that he would " 
+ _
		"shortly be celebrating his eleventy-first birthday,"
	clause2 = " there was much talk and excitement in Hobbiton"
	oText.setString(clause1 + clause2)
	
	oCursor = oText.createTextCursor()
	oCursor.gotoStart(false) 			'false: nicht markieren
	oCursor.goRight(len(clause1) - 1, false) 	'ans Ende von clause1

	oText.insertString(oCursor, _
		" with a party of special magnificence", true) 'true: markieren
'--------------------------------------------------------^^^^^ 
' the above use of true has no effect, no selection is made

	oCursor.setPropertyValue("CharWeight", _
		com.sun.star.awt.FontWeight.BOLD)	
'-------------------------------------------^^^^ hence bold is not applied
End Sub

Sub UseSpreadsheetDocument
	Dim noProps()
	oServiceManager = getProcessServiceManager() 'fest eingebaut
	oDesktop = oServiceManager.createInstance("com.sun.star.frame.Desktop")
	oDoc = oDesktop.loadComponentFromURL("private:factory/scalc", _
		"_blank", 0, noProps())
	oSheets = oDoc.getSheets()
	oSheet = oSheets.getByIndex(0)
	oCell = oSheet.getCellByPosition(0, 0)
	'oCell.setPropertyValue("IsTextWrapped", true)
	ManipulateText(oCell)
End Sub