assigning multiple tasks to a single resource results in overload

 Here's my use case...

I have a series of 10 tasks in a milestone. 

• The milestone's start date is inherited from the start date of the project. 
• The Milestone's work policy is fixed duration, and it's a rollup of the ten tasks. I presume that means it calculates its duration from adding up that of the ten tasks. 
• Each of the ten tasks inherits its start date from the milestone. 
• Each of the ten tasks has a work policy of fixed work, which I set. 
• The work value has been set to estimates provided by the resource that will be assigned to the work. It's stated in hours, and represents the amount of time that the resource will be heads down, working on the task. 
• I have assigned the same resource to each of these tasks. 
• That resource has a maximum allocation of 55%
• I let Clarizen calculate the duration. BUT....
• It set all 10 tasks to start on the same date, AND
• it set the due date based on the duration calculated for that task. 
• That resource is completely overloaded 

So, it's as though CZN is treating this resource as a different person. I suppose I could set each task as a predecessor to the next, but since it's the same guy with the same max allocation, I'd figure CZN would just push each task downstream after the next was completed. 

Is there an easier way to do this?