I am trying to write words like dyūtam in nāgarī in MS Word (using Keyman) but I end up without the ligature: it seems that whenever d is followed by consonant+u/ū/ṛ, the d ends up followed by virāma. This affects things like dyū, ddhṛ, etc. I will type the nāgarī here, but your systems may well correct it:

द्यूतम्, -अद्बु-, -अद्धृत-

When followed by -a-, the ligatures dy, db, ddh, etc come out correctly, but they split (into d-virāma-y etc) as soon as another vowel follows.

Even if I copy and paste the correct ligature from e.g. the Cologne dictionary, it splits when pasted.

Can anyone recommend a solution to this problem? My font selection seems to default to Nirmala or Kokila when writing in nāgarī, but perhaps there is a better Unicode font out there that has a wider range of ligatures? 

I prefer not to use Word, but in this case there is no choice...

Thanks for any suggestions,

John