Hi Maarten,
I'm posting this bug here
Not sure this can really be called a "bug"… your input syntax is
somewhat confusing.
In particular, it looks like you want polyphony, but aren't actually
coding polyphonic voices (which would require a \\).
Here is a possible modification which is actually valid polyphonic
syntax:
\version "2.12"
\paper {
ragged-right = ##t
}
\score
{
\new Staff
{
\set Staff.instrumentName = "Strange things"
\relative c''
<<
{ \voiceOne
as2 ~ as2
} \\
{ \voiceTwo
fis16 e16 d16 e16 ~ e4 ~ e2
}
>>
}
}