I don't have an answer but want to add a +1 in the hopes of getting one.
Thanks for bumping this one Jon. I put this aside and never got back to it. I didn't watch the videos you referenced, so I'm not sure what they're telling you to do, but here's how I do these sorts of visualizations:
1. Create an Excel spreadsheet having column header of the marks you'll want to show and an X & Y axis. In your case it will look like this:
Note, it only has one line at this point, the most important part is the X & Y axis are the size of your image expressed in pixels. The other stuff is just filler.
2. Connect to this file, and put the X on column and the Y on rows (I just got through confusing these this morning). Change them to MAX(X-AXIS) and MAX(Y-AXIS)
3. Go to Maps\Background Images and go to this dialog box:
4. Browse to the image and then fill in the fields like I show in yellow.
5. Click the Options tab, check both options.
6. As you click OK you should get this:
When you click apply, then the image should appear in the background.
7. Now comes the fun part. Right click the image where ever you're going to want a mark, and click Annotation, and then Point. Keep all the fields, but make the font size bigger (old eyes). Click OK and you'll get something like this:
8. Put those two numbers in your spreadsheet, along with the Room and Location info you're wanting.
9. Now move the arrow end of the line to another location, you'll get something like this:
10 Enter these into a new row on the spreadsheet, repeat as often as you need.
11. Once you've got them all done, refresh the data source, add the Room & Location fields to the viz wherever you want. And you're done.
The trick to all this is to establish the background image first, then figure out your mark's x/y coordinates. Holler if you have questions,