Use Current Date to Trigger Action

Greetings! I created a page with 12 images representing each month in a year. They will animate in as audio narration is playing. I could just animate them in one at a time starting with January, but it would be cool to start the graphic on the month that the course is accessed. So if it's accessed today, the first month to appear would be August, then populate through July. As a test, I created an OnShow action to show the August graphic if variable CurrentDate contained August. I also tried <August>. When those didn't work, I created a hidden text box to contain the current date and a ChangeContents action to update it with CurrentDate. None of these worked.

Once I determine that I can do that, I need to figure out the best way to trigger the proper order regardless of the month. My thought is to create one action group for each month that plays the images in order, then use the OnShow Action to determine which one to play. My concern is that it might take a long time to process that calculation. I'm open to ideas.