The Kickstarter project Endangered Alphabets II: Saving Languages in Bangladesh might be of interest here.
In short, their aim is to record the Indic alphabets used by the indigenous languages spoken in the Chittagong Hill Tracts of Southern Bangladesh, such as Mro, Marma, Tripura, and Chakma. The project creator Tim Brookes will carve signs using these alphabets for his Endangered Alphabets exhibition, and a typographer and a calligrapher will collaborate to produce typefaces that can be used to print children's schoolbooks in these languages.
The project description page is somewhat vague about just how endangered these scripts and languages are and what the current situation is, so I've drawn up a quick background about the four languages mentioned.
Mro is considered "definitely endangered" by UNESCO, with around 50,000 speakers in Bangladesh and Burma. The proposal for encoding the Mro script seems to be still in the Unicode pipeline at this stage.
The Marma people numbering around 210,000 are Arakanese (Rakhine) descendants living in Bangladesh, and therefore speak a form of the Arakanese (Rakhine) language, which is itself a form of Burmese, written with the Burmese script. I couldn't find any mention of a separate alphabet for the Marma people.
"Tripura" seems to be referring to Kokborok, an official language in the Indian state of Tripura. Only around a tenth of the 800,000 total speakers of Kokborok are in Bangladesh. Kokborok was once written in its own script called Koloma, but this has disappeared and it has been written in the Bengali script since the 19th century. The Latin alphabet was also introduced later, and both Bengali and Latin are used today, with the choice of script a highly politicized issue. I couldn't find any information on the situation in Bangladesh.
The Chakma language has around 700,000 total speakers in India, Bangladesh, and Burma, with around 310,000 in Bangladesh. The Indian state of Tripura announced in 2012 the introduction of Chakma language in primary schools. The Chakma script was added to Unicode 6.1 in January 2012.
To summarize, only two of the four languages mentioned (Mro and Chakma) have their own scripts currently in use. The other two are written with Burmese (Marma) and Bengali or Latin (Tripura), which as scripts are not particularly endangered. Nevertheless, there may be variants of these scripts particular to these languages as used in Bangladesh, just as there are different variants of the Latin, Cyrillic, or Arabic alphabets depending on the different languages that use them. Mro is by far the most endangered of these languages; the other languages each surpass Icelandic in total speakers, for comparison, although it has to be pointed out they are not officially recognized in Bangladesh and are threatened by the official national language of Bengali, which is understood by 98% of the population.
