When using the "Open Project..." function on a project without a .q file, the
current working directory is not used in "Open Query...".

Description provided by Ferdy Hanssen:

Start Uppaal, open a project with "File -> Open Project...".

There are two possibilities now.

You choose a file zzz.xml with a complementary zzz.q being present in the
same directory, the "Queries -> Open Queries..." dialog opens in the same
directory as where zzz.{xml,q} are found.  The queries from zzz.q have in
this case already been loaded into the verifier window.

You choose a file zzz.xml WITHOUT a complementary zzz.q being present
there, then the "Queries -> Open Queries..." dialog opens in my home
directory, where I would expect the current working directory when Uppaal
was started.