Ok. Swimlane text is not rotatable today, but you can stretch your swimlane title to take up the entire vertical space on the page. Let me ask you a few more questions:
1. How many swimlanes do you currently have from top to bottom? 2. What MS Project field you using to group your swimlanes today? For example, you can group swimlanes by task name, phase, outline level, resources, etc.
One thing you can do is merge the mutiple swimlanes into a single swimlane that you can then use for a side title. Just left-click on both swimlanes, while holding down the Ctrl key, right click on the selection, and merge the swimlanes together.
If you'd like some more detailed instructions, go ahead and send us a screenshot to support@chroniclegraphics.com and we can take a look at your specific chart to give you a pointer or two.