I tried to do something along these lines when the grid was 25x25 - but impossible. Now with a bigger grid I thought I'd give it another go. I used to love the Beat and the Specials... lots of memories for me. It says there are multiple solutions but I've tested a couple of times and only get the one solution (so here's hoping you do too!)
Il y a effectivement deux solutions possibles selon que le deuxième 1 de C27 est placé en L13 (bonne solution) ou en L15. Cela joue sur les 6 ou 7 derniers points mais tout le reste est impeccable !