This is a bit hard to say without seeing your actual modifications.
Let's try the following (I started with a blank MPTW*)...
In your [[MptwPageTemplate]], find the following line:
---------------
<!-- <div id='mainMenu' refresh='content' tiddler='MainMenu'></div> -->
---------------
... and replace it with something like this:
---------------
<div id='mainMenu' refresh='content' tiddler='NavMenu'></div>
---------------
Then add the following to your [[StyleSheet]]:
---------------
#displayArea {
margin-left: 14em;
}
---------------
Next, create a new tiddler [[NavMenu]], and put in there whatever
content you want on the left-hand side.
HTH.
-- F.
Rather than using the presentational "style" attribute, you should add
the CSS code to your StyleSheet. Among other things, this will make it
easier to modify later on.
We defined the element's ID as "mainMenu", so the corresponding CSS
selector and rule set would look like this:
#mainMenu {
font-size: 0.9em;
}
HTH.
-- F.