TextPad comes with two dictionaries (for the version I'm using, anyway) This is great because we have the option of using English (USA) for those of you in the USA, and English (UK) for the rest of the english speaking world.
However... If you select the "Language" item in Preferences (for user interface), you are presented with only "English". The downside of this is that it isn't English after all, but American. I'd like to suggest that the entry be renamed to "English (USA)" and an "English (UK)" entry added. TextPad is my favourite (favorite) editor and is greatly customisable (customizable), but this would make it closer to being fully localised (localized). I also found the following in textpad

Capitalized -> Capitalised
Minimize -> Minimise
?ize -> ?ise (You get the idea

Center -> Centre
Color -> Colour
Not too sure on Dialog -> Dialogue This may be microsoft's fault I guess.
Millimeters -> millimetres
Come on... if you refuse to convert to metric like everyone else, then at least refrain from changing our spelling! (vents litres of steam!

I almost fell off my soapbox when I found "Unrecognised" on the same screen as "Capitalized"

If you find any other American words used in place of English words then email me at Flavour@Odour.Color.com.us