UltraEdit prior v11.00 uses original Htmltidy.dll from
Dave Raggett which must be downloaded and copied manually into the UltraEdit program directory. Well, currently latest version 16.00 of UltraEdit and all previous versions still support this DLL by command
RunHTMLTidy which can be used via a hotkey, see key mapping configuration. This (old) version of HTMLTidy requires creating a configuration file manually which must be specified by editing uedit32.ini manually and inserting the line
Html Tidy Config File=Full name with path of the manually created configuration file for HTML Tidy
under section
[Settings].
Starting with UltraEdit v11.00 the HTML Tidy support has been improved by using
tidylib.dll from the
SourceForge HTML Tidy project. The DLL is automatically installed with UltraEdit. And the user can configure the options directly in UltraEdit or use a manually created configuration file. From UE v11.20 to v15.20
tidylib.dll is HTML Tidy for Windows vers 12 April 2005.
With UltraEdit v16.00 and UEStudio v9.30.0.1004 the name of the DLL changed. Instead of
tidylib.dll now
libtidy.dll is installed during installation of UltraEdit/UEStudio into the UltraEdit/UEStudio program directory and is used by UltraEdit/UEStudio.
libtidy.dll of UE v16.00 and UES v9.30.0.1004 is HTML Tidy for Windows vers 25 March 2009.
To answer finally your question: Rename
tidylib.dll in the program directory of your UE v14.20 for example to
tidylib_bak.dll and copy latest version or German version into the program directory of UltraEdit with the name
tidylib.dll. Then test if you can use that DLL from within UltraEdit by executing HTML Tidy. When it works, fine, otherwise you are out of luck and better use the command line version of HTML Tidy via a user tool.