Create Khmer Spelling Checker Add-in for MS Word with Hunspell and VSTO + C#/VB

General information for the business: The Society for Better Books in Cambodia helps create OpenSource solutions for publishers and translators to produce high-quality Khmer resources.
Kind of development: Customization of existing program
Description of every module: Integration of existing program (Nhunspell) with a new Microsoft Office Addon to spell check Khmer documents in Microsoft Word 2010 and above.
Description of requirements/functionality: Create a functional spelling checker for the Khmer language for Microsoft Word using Hunspell (specifically .NET Hunspell).
The spelling addon should work with Microsoft Word 2010 and above. As far as what the addon should look like – We would want it to match the default Microsoft spell checker as much as possible. So to have a dialogue box as the default spell checker with a box of suggested words (Hunspell does this already, so it is just a matter of getting the results from Hunspell), and then an ignore, change, or add (this would add the word to a user dictionary). We don't know if it is possible to have the addon check spelling as the user types, but if that is possible that would be great (with a red underline when a word is wrong, and a right click would bring up the suggested words, ignore or add as well).
Microsoft Word does a good job of detecting if text is Khmer or not, so if the text is not Khmer, the spelling checker should not check it and skip over it until Khmer is detected again. Khmer uses Zero Width spaces between words rather than traditional spaces.
Details can be discussed as needed and sample Khmer Word document is attached.

The Khmer language currently has a spelling checker that we developed for OpenOffice using Hunspell. We developed the spell checking dictionary to help ensure high quality resources were being produced by our organization as well as to help others spell check in Khmer (it is available for free download here: http://www.sbbic.org/2010/05/27/open-office-khmer-spelling-checker/)

But most people use Microsoft Word and it is hard to always install OpenOffice on their computer (and OpenOffice sometimes has bugs working with long documents in Khmer). There is no viable solution for spell checking Khmer in Microsoft Word which makes our editing process more difficult as well as more difficult for all Cambodians.

We need a programmer to create a solution to integrate the Khmer Hunspell dictionary into Microsoft Word as a spelling checker (a .net Hunspell exists here http://nhunspell.sourceforge.net/). We realize this could be a very difficult project, but as we are a non-profit, we do not have much funds to use for this project.

Basically, what you need to do is as follows:
· Use the .NET version of Hunspell

· Need Visual Studio 2010+ to develop a VSTO Word application Add-In.

· Create a Word Add-In, that addresses all DOM objects in a given active Word document.

· Also need a way to identify if a word is Khmer or non-khmer (via UNICODE codes of characters).

· Loop over all Khmer text in the active document and check the spelling via Hunspell library referenced in the Add-In project.

The resulting program will be given out for free download to anyone who desires to use it, and we would like the code to be open-source if possible as well so that other languages can benefit from the work.

Thank you for your consideration.
Specific technologies required: Hunspell, .NET, VisualStudio, Microsoft Word, C# and Visual Basic
OS requirements: Windows
Extra notes: