As you are having trouble with text in a cell or merged cells, how about putting your title text into a text box, and setting the text box to not change size with the cells.
From the Ribbon select Insert, then Text and the 'Text Box'.
Draw the text box to the required size and shape.
Enter the text then select the text to choose font, font size and font color.
Right-click on the text box outline and select 'Size and properties'
In the Properties tab choose 'Don't move or size with Cells' Click OK
You can also right-click the text box outline and select 'Format Shape' to adjust the outline - line color, 3D effects etc.
Hope this does what you want.