To utilise the patch, apply it to the nedit-5.5 source (eg nedit-5.5-src.tar.gz), then modify an Xresources file (and place in $HOME). Note, to compile a working version of nedit against openmotif on EL6 (without the infamous copy and paste bug), see my previous post (http://richardbrucebaxter.blogspot.com.au/2012/04/nedit-copy-and-paste-bug-workaround.html).
"How does one navigate multiple recently used files/tabs? MS Visual studio provides this functionality with Ctrl-tab. The only option provided by Nedit at present is to disable tabs and use alt-tab. The problem with this work around is that if a significant number of files are open in nedit then it requires a window manager that supports grouped task bar items. Nedit is therefore incompatible with icewm on even moderately sized projects."