I've tested nitroluks on Ubuntu 18.10 and it doesn't break anything. But I found a few (minor) issues:
/etc/crypttab in Ubuntu should have the following format:
<device>_crypt UUID=<DISK-UUID> none luks,keyscript=/usr/bin/keyscript.sh
/lib/cryptsetup/askpass: the "\n" is disregarded in the string (no line break) in keyscript.sh, but askpass seems to work otherwise (falls back to passphrase, if no nitrokey is present)
/bin/nitro_luks and echo don't work with plymouth (you are stuck during boot at the splash screen and have to hit escape)
I've tested nitroluks on Ubuntu 18.10 and it doesn't break anything. But I found a few (minor) issues:
<device>_crypt UUID=<DISK-UUID> none luks,keyscript=/usr/bin/keyscript.sh