Liaisons in the Voynich text

[ololololo]

but also clear prohibitions against certain configurations?

It’s not entirely clear. The manuscript contains a very small number of non‑standard words, such as saino, the form of which doesn’t really fit the structure of Voynichese words.
However, there are definitely some restrictions:

Only a or o can come before iin; there are no words like tiin, eiin, or yiin. However, it is acceptable for letters or digrams to appear after iin: daiindy, saino.

Two gallows cannot be placed consecutively (like ttchor or kpaiin).

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I find the possibility that certain combinations are avoided because they contradict the construction rules of the script very fascinating.

This is because the VMS text is structured. This is not absolute nonsense as aiiij klopy olalaysa
This must be taken into account when creating a text generator.