Added a huge (german + chinese) poster with all cast credits at http://hkmdb.com/db/movies/images.mhtml ... ay_set=eng
(hope You don't mind the German Title). It seems much better to me than the recent poster - please compare - that's why I replaced it.
Anyhow that movie has already a nice extern gallery with many gaps - say missing actors and not made ID's yet.
I always wished to get a HKMDB gallery for that one and may be we can close some unknown actor files then? I made some research allready and guess I made ID for the actress....

02 王羽 Jimmy Wang Yu
01 郭å°

I agree with Chun Mat, but I do not think your tentative ID's for 4, 5, and 15 are correct. I watched this movie again a few days ago; it may be difficult to get good images for some cast members. (The actor who played Sun Yat-Sen is probably in the cast, but we never see him close-up on the screen.) I will do HKMDB images for this film, and will try to get many images.

Images added for Chow Ken
http://hkmdb.com/db/movies/images.mhtml ... ay_set=eng

The first 5 unknowns have the most prominent roles among them.

These are the names on the poster which are not identified in the film:
Gam Sek
Chow Chi-Kei
Kon Tak-Mun
Wei Siu-Gwan (probably Cheng Siu Gwan)
Cheung Yee-Boon
Dung Gam-Woo
Yeung Lee-Gwan
Lok Ming

I am familiar with Gam Sek and Kon Tak-Mun, but I did not see them. Some of the other unknowns have suspected identification, but I am not confident enough to identify them.