The builtin routes "2-to-16-max-4-direction-changes.route" and "2-to-32-max-5-direction-changes.route" are to big, and cause a freeze under Linux.
A workaround is to split the routes into smaller pieces. (< 4096 bytes)
split routes/2-to-16-max-4-direction-changes.route -l 810
This creates four files of 3223, 4050, 4050 and 395 bytes.
I've also tested a file with 4095 bytes, which will work.
As soon as a file reaches 4096 bytes, kwp will get stuck.