Hi @ONEproject, thanks for taking the time to report this!
@ONEproject: Do you plan to fix this yourself? Asking as you set yourself as task assignee.

Please provide exact license information for the proposed font(s). They must be under a free software / open source license.

Within many code pages, CMs (Classical Mongolian script) by Peter Cheung (aka dEgi, Taiwan) became de facto for DTP applications, digital typesetting and word processing in Mongolia until Microsoft Vista`s built-in IME support was released. A set of TrueType font CMs Ulaanbaatar, CMs Huree and CMs Urga (1998) is widely used because of its simplicity: no need of extra keyboard drivers and programs. Thousands of contents are stored in this codepage and in CMs fonts. Orthography dictionary of UNESCO project , Lingua Mongolia Mongolian-English Dictionary and many more systems are utilizing CMS codepage. Thus, developing CMs support scheme for TMSDL is becoming crucial matter in terms of content enrichment of TMSDL and disambiguation of words which have same pronunciation by using orthography dictionary .

You can see table https://docs.google.com/spreadsheets/d/1xRPDcyzKMb0nyBDnyyu8ACxmPdQdjWk6J9rDSFeYUdE/edit#gid=0
CMs Ulaanbaatar font is not commercial font. It's "Personal Use" like as "Arial" etc (http://www.fonts2u.com/cms-ulaanbaatar).

Additional References:

A Study of Traditional Mongolian Script Encodings and Rendering: Use of Unicode in OpenType fonts in reference of https://en.wikipedia.org/wiki/Mongolian_script

https://books.google.mn/books?id=puNtCQAAQBAJ&pg=PA45&lpg=PA45&dq=%22Peter+Cheung%22+%22CMs+(Classical+Mongolian+script)%22&source=bl&ots=XuqOLCTFGE&sig=ia6a4wLqe0XNT1dd49fj2Y_ei48&hl=en&sa=X&redir_esc=y#v=onepage&q=%22Peter%20Cheung%22%20%22CMs%20(Classical%20Mongolian%20script)%22&f=false

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&ved=0ahUKEwiw-PnJq9HLAhUB4qYKHS0aD0QQFggwMAQ&url=https%3A%2F%2F14513011872770600930.googlegroups.com%2Fattach%2F209a1ee65dd9b37%2FMongol%2520bichig%2520encoding.docx%3Fpart%3D3%26vt%3DANaJVrE_zNzUNk6v6tCZ0sl4zX7hcROChXZ2mFjuLYmjGVwiHGlx2spcNQjrDByzcoLeopGHDJYAySNlQb3v5EwFMKzagWwTmUr8Md9D6cYhpVHe2PalUes&usg=AFQjCNFI8fTB4RoCiBZjJN60coLZtiE_pQ&sig2=GxRiM3bV4V0NOnw4_on03w&cad=rja

http://www.free-fonts.com/font/cms_ulaanbaatar.html
http://www.fonts2u.com/cms-ulaanbaatar
http://www.fonts2u.com/cms-ulaanbaatar-dp.fonte
http://www.typ.com/font/cms-ulaanbaatar
http://luc.devroye.org/mongolian.html
http://luc.devroye.org/fonts-31809.html
http://www.fontineed.com/font/cms_ulaanbaatar_1
http://www.mongolei.de/service/mn_fonts.html
http://www.omniglot.com/charts/fonts.htm

@ONEproject: Do you plan to fix this yourself? Asking as you set yourself as task assignee. Also, please provide exact license information for the proposed font(s), as "Personal use" is not a license in itself. :)

@ONEproject: Could you answer my last two questions please?

@ONEproject: Please answer my previous questions so we can proceed here.
Otherwise we must decline this task. :(