Excel 2007 VBA and 2010 VBA: NOT a well thought out platform for my userform

I'm not prone to panic, But... I've designed a pretty good userform for a comprehensive work task.
It was created using Excel 2007 and the code works like a champ... (on Excel 2007)!

Today, I brought the spreadsheet into the office for a test run... where they all use Excel 2010

Problem is - soon as the dang userform loaded... "BAM" a date format issue, then a compile issue...
I was ready to go home 15 minutes after I clocked-in!!


I just don't understand, or know where to begin - I just can't believe that I need to restructure or rewrite the entire code just because I'm trying to run the dang thing in another Microsoft Excel Environment!
Then what - I need 2 copies??? 1 for 2007 and 1 for 2010???
Bull. There has to be something I'm just not aware of.

What are some answers from the guru's?
thx much

Please pardon my obvious frustration, but I've been tweeking this thing for months on Excel 2007.