Hello,
In Windows Vista 64-bit, there is no config.nt available, since 64-bit Vista will not be allowed to run 16-bit programs, not even in "DOS" mode. If your old MS-DOS application (AccPac Plus) is a 16-bit application, I don’t think that it could work well under Windows Vista Ultimate 64-bit.
To the issue of creating shortcuts, you might test the problem on some other applications. If the issue only occurred with AccPac Plus, you'd better contact its own support to solve the problem in timely manner or confirm whether the application has the 64bit edition. Thanks for your time and understanding!
Good Luck!
Andy