Oh well, I made a mistake (better really test the code next time).

I couldn't come up with a solution dropping the .*?, so Tachyon-II's solution only needs a slight modification ...

...
my @arr = $string =~ / .*? [KR] (?!P)  | [^KR]+$ /gx;
...
[download]

... for getting the strings tail.

Thanks for checking this!

Regards

mwa