Hi Richard and All,
Please see interesting results on Bengali character sequencing (rules) while using U+09CD followed by U+200C (zero-width non-joiner) or by another Bengali
character, for an example, a charcater sequence  বাদ্লা  (Badla or rainy).
  
বাদ্লা  (U+09CD not followed by U+200C)

09AC:   ব  BENGALI LETTER BA
09BE:   া  BENGALI VOWEL SIGN AA
09A6:   দ  BENGALI LETTER DA
09CD:   ্  BENGALI SIGN VIRAMA
09B2:   ল  BENGALI LETTER LA
09BE:   া  BENGALI VOWEL SIGN AA
0020:      SPACE

বাদ্‌লা  (U+09CD followed by U+200C to get no Conjunct)

09AC:   ব  BENGALI LETTER BA
09BE:   া  BENGALI VOWEL SIGN AA
09A6:   দ  BENGALI LETTER DA
09CD:   ্  BENGALI SIGN VIRAMA
200C:   ‌  ZERO WIDTH NON-JOINER
09B2:   ল  BENGALI LETTER LA
09BE:   া  BENGALI VOWEL SIGN AA

বাগ্মী  (U+09CD not followed by U+200C resulting in a Conjunct গ্ম )  

09AC:   ব  BENGALI LETTER BA
09BE:   া  BENGALI VOWEL SIGN AA
0997:   গ  BENGALI LETTER GA
09CD:   ্  BENGALI SIGN VIRAMA
09AE:   ম  BENGALI LETTER MA
09C0:   ী  BENGALI VOWEL SIGN II
0020:      SPACE

বাদ্লা  (though U+09CD is not followed by U+200C, it results no conjunct)

09AC:   ব  BENGALI LETTER BA
09BE:   া  BENGALI VOWEL SIGN AA
09A6:   দ  BENGALI LETTER DA
09CD:   ্  BENGALI SIGN VIRAMA
09B2:   ল  BENGALI LETTER LA
09BE:   া  BENGALI VOWEL SIGN AA
0020:      SPACE

বাগ্‌মী  (U+09CD followed by U+200C resulting no Conjunct, as expected)

09AC:   ব  BENGALI LETTER BA
09BE:   া  BENGALI VOWEL SIGN AA
0997:   গ  BENGALI LETTER GA
09CD:   ্  BENGALI SIGN VIRAMA
200C:   ‌  ZERO WIDTH NON-JOINER
09AE:   ম  BENGALI LETTER MA
09C0:   ী  BENGALI VOWEL SIGN II