Chart elements altered in 2010

We just upgraded this morning from 2003 to 2010 (well, my group did; my users, for the most part, will be on 2003 for the next 6 months). I was anticipating macro problems, but I'm doing okay on my macros. However, I'm having problems with a chart (charting is one of my weakest areas in Excel; I'm pretty much clueless here). I put the chart together over a year ago, with a lot of help from this forum, and have macros that update it on a daily basis. The macros appear to work just fine in 2010, but the chart is a goner.

The attached file has two parts, a Word doc showing the view for a 2003 user vs the view for a 2010 user, and the 2003-formatted workbook containing the chart. In the workbook, I can see that one problem is that the Y-axis has changed, but I'm not sure why it changed. I can fix it by putting in a fixed 0 for the minimum, and 1.0 for maximum, but I'm very unsure that if I do that it will continue to show correctly for my 2003-users.

The second problem I don't know how to fix at all. That's the blue line across the middle of the 2003 view. That shows where we are in the fiscal year (percent of FY passed). If I fix the Y-Axis, my blue line disappears. If I make any kind of change in the blue line, it moves over to the right.

Again, charts are very hard for me, so any help (the more explanatory the better) is IMMENSELY appreciated!

Thanks,
John