[AccessD] MDB on Office 2010 Professional Plus

I have one customer left from the now-long-ago days when I did Access
development fulltime.
 
He is having trouble because one of his customers is now running Windows 7
(64-bit) using Office 2010 Professional Plus (64-bit).  
 
Our little app, in Access 2003 format, won't even open.  Access opens, but
our splash screen doesn't appear.  
 
I don't have 2010 installed, so I don't even have a place to try to fool
with this.  Yet, I suppose.
 
Does anybody have experience with this issue?  Any workarounds?
 
Thanks,
 
Liz