http://hkmdb.com/db/movies/images.mhtml ... ay_set=eng (It has no one-armed swordsman even)
Who is Chong Sou?? I can't tell..(Who was Liu Yan?)

?? is character from the novels of Liang Yu Sheng. Liu Yan is not a name in the standard sense. My guess it's more like a title, like The Cause or The Reason or whatever '?' means. Just my thought.

According to the hkfa film synopsis, he is "the traitorous disciple". Also, "the noted sage Nin Kang-yiu (Kwan Hoi-San) is interrupted by Liu's trespass on the secret site."
From that, it should be easy to ID him by watching the movie.

Also, from his character bio, Yu So Chau is his apprentice?
??????????

Added to the cast Kong Man-Sing, Wah Wan-Fung (no image ID), Gam Lau and SB-Actor 18

Thank You for Your help - but still the story was impossible for me to follow (no subs) Cantonese and bad sound and seems the actor was never adressed by his name. I suppose it must have been this one who had a prominent part who fought the heroes..
http://hkmdb.com/db/movies/image_detail ... ay_set=eng

i will add to my 'to watch list', TBD. I like to watch full movie before making my cast images. Usually 2-3x to best understand and ID, that is my method for subless Cantonese movies. Yes, it is time consuming but better for accuracy. If you are not sure please do not tag. "Measure twice, cut once."

As You like - I won't suffer through that movie once more there are tons of other movies yet still