ligature or not

hello everyone. i reposted this here because i had it in the wrong thread at first. my bad.
i started using fontlab a while ago and have run into a brick wall. i am in the process of creating a non latin font and have an issue i wish to seek advice for. the font uses an alphabet which works the way korean hangul does just not as complex. in other words it creates syllable blocks. i have glyphs for each of the individual vowels and consonants and have created ligatures for the basic cv and cvc syllables. my issue arises when for example i try to write a word like "baba". i have a glyph for “b” and one for “a”. when i write “b” and “a” together i get a new glyph in my output window for "ba" which exactly what i want. however i also have a glyph for "bab" which is what i want the output to be when i write “b”+“a”+“b”. again this is fine. the crux comes about when i wish to write ”b”+“a”+“b”+“a” i want the glyphs to show up as "ba” “ba" not "bab” “a" which is what happens. i don't know how to tell font lab that when a two syllable word is written to use a cv+cv combination rather than a cvc+v combination. maybe ligatures are not the way to go. i have tried playing around with dlig's and salt's, but am no closer to solving my issue than i was when i discovered it. maybe i need asia font studio instead of fontlab. i hope not. if this can be achieved in fontlab then any help in this regard would be much appreciated. thanks all!