[AccessD] RunTime and multiple clients with different Access Versions

While I have now and then had the hubris to think that I know what I'm
doing in Access, a friend and colleague posed a question or two to me, to
which I found I had no solid answer, so I'm reaching out to my beloved
community for some insight.

Here are the problem's parameters:

1. The app is a vertical-market thing written in Access and deployed using
RunTime.
2. Some but not all the customers have various versions of Access installed.
3. Being an old-timer, my friend still works mostly in Access XP or 2003 or
whatever its correct name is.
4. Many of his customers have not moved beyond this version, but lots have,
and he is experiencing problems due to this. Not serious problems, but
rather annoying messages that mention "installing" and bla bla bla if said
clients are running a subsequent version to his preferred dev-version.

Preferred solution if possible:
1. Avoid these annoying "intalling" messages on all versions of both
Windows and Office.
2. Avoid version-specific builds; build once and it works on all versions
of both OS and Office.
3. Handle References problems transparently without user-intervention.

Is there some recipe that can make this possible? I personally have never
faced this issue, primarily because I do one-offs and do not attempt to
sell a product into a vertical market. So I have little or no experience
confronting these issues. From my limited experience in this area, I have
almost always stubbed my toe when (on my dev box) trying to run 2003/XP
alongside 2007+. Whenever I've tried this, I have always been delayed by
Office's attempt to reconfigure itself. The only method that I have found
so far that works is to isolate the versions inside separate VMs; but that
sucks.

Any suggestions gratefully accepted.

-- 
Arthur
Cell: 647.710.1314

Prediction is difficult, especially of the future.
  -- Niels Bohr