Phew. Late night debugging showed that the ray casting code I used for line of sight was hilariously broken since the first usage years ago for straight vertical or horizontal lines. Good fun to debug 
Anyhow, line of sight now seems to do what I want. I also managed to get the complete, fail and total win conditions in and get the menu stuff out of may way. All in all I have a short game of five stages that could well be a final entry. Of course I do hope to spend a bit time on more and bigger stages!
The game has thusly been dubbed Assassins'r'Us.
To be safe I uploaded a current preview version with the five stages I have. The game is mostly feature complete (but one feature I'd love to add) and can properly be played. In case I don't have any more time this would be my final entry. The submission is over at https://neonlightgames.com/woa/Submissions
A safety backup is also at www.georg-rottensteiner.de/files/WoA5_Endurion_AssassinsrUs.zip
Really nice and fun to play!
I had a few issues though: The main download link didn't work (corrupted zip) but the backup worked fine. Rotate left/right key bindings were not set initially and jump seemingly doesn't work (tried changing the key binding but still no joy).
Also in writing this I accidentally knocked my mouse on the floor and it broke, so onto mouse #2.