1. Export with
Modelviewer as a .mqo file.
2. Open the .mqo in
MetasequoiaLE* and re-save.
*The registered version supposidly exports as .obj but I haven't been able to test it. There is also no current way to get a registered version as the author won't accept international payments.
3.
Shade* can import .mqo (originally a Japanese program) and export as different formats including .obj You will need the
mqo plugin.
*Trial version available for download, but haven't tested it and I don't know what the limitations are.
3a. There may be a program that can convert from one file format to another, but currently I have not found any that works between mqo/3ds/lwo/obj
You could ask around the Maya development community and see if there are any plugin writers that might be able to figure out how to make one. The author has the source available on his site if they could make use of referencing how the MAX plugin works.
http://sio29.sakura.ne.jp/maxplg/maxplg.html
3DStudioMAX6用プラグインのソース
mqoimp6_108_src.lzh