help in R 2.9.x for R 2.10.x packages

[Env: Win Xp]
Is there any options() setting or call to help()  or help.start() that 
will allow me to view a help file for
a package built under R 2.10.x under R 2.9.2?

I'm using both R 2.9.2 and R 2.10.1, but prefer the former because the 
CHM help is so much easier
to use. Yet, if I install a package built for R 2.10.x, I can't find 
*any* way to display a help file in this
package.

For example, after library(TeachinDemos),

 > ?HWidentify

Error in print.help_files_with_topic(x) :
  No text help for 'HWidentify' is available:
corresponding file is missing
In addition: Warning message:
In 
print.help_files_with_topic("C:/R/R-2.9.2/library/TeachingDemos/chm/HWidentify") 
:
  No CHM help for 'HWidentify' in package 'TeachingDemos' is available:
the CHM file for the package is missing

So, I try

 > help.start()

updating HTML package listing
updating HTML search index
If nothing happens, you should open 'C:\R\R-2.9.2\doc\html\index.html' 
yourself

I can then get to
file:///C:/R/R-2.9.2/library/TeachingDemos/html/00Index.html
but then all the links there give Not Found, e.g.,
file:///C:/R/R-2.9.2/library/TeachingDemos/html/HWidentify.html

and, indeed, C:\R\R-2.9.2\library\TeachingDemos\html contains
only 00Index.html.
All the links therein are to .html files in the same directory, so of course
are wrong.