apertium-init for bilingual modules currently works well as long as monolingual modules are also created by apertium-init (or have a very similar setup).

However, many monolingual modules have no pgen (no need) or no rlx (only prob) or no prob (only rlx) files. It should be possible to create a bilingual module where we one of the monolingual parts is "incomplete" in this way.

The interface should be like "apertium-init foo-bar --no-rlx2 --no-pgen1 --no-prob1" where foo and bar are language codes and apertium-foo has no post-dix nor .prob and apertium-bar has no rlx file.

This will require changes to the bilingual modes.xml as well as Makefile.am.