In short, no as it's more about it being locked down than the fact it's a word processor.
As I say, if you have a multi-use exam device i.e. one day spellcheck, the next no spellcheck, the next day spellcheck with reader etc. - it becomes troublesome for some software as generally GPOs are computer based, rather than user based and settings may choose to stick. The point of having something like ExamPad+ do it would be we get to configure those options on a whim regardless of user AND have universal software for digital exams. Rather than have to use say Secure Exam Browser for one exam, and WordPad+ for another for already confused exams teams/students.
Thinking out loud, it would have to be exportable as a PDF rather than .epp - so imagine this isn't of significant interest now. More people are moving towards the web app instead. Depends if AQA and other exam boards go the PDF or WebApp route though (most likely the latter).