In this thread you can get general support for Share.
English localization and startup guide:
http://www.uguu.org/share/
Wikipedia entry:
http://en.wikipedia.org/wiki/Share_%28p2p%29
a) Wierd... i tested seting netlimiter to 1ks/s upload and the download increasely fell down... I have a thought that this has something to do with getting poor download speed.
b) So which por should i open?
Share need some upload bandwidth to communicate with other nodes, so don't go cap it at 1kb, keep it at around 10kb (I can max my down stream easily while capping upload at 10kb, YMMV though).
As for port for Share open the one you set up in Share options.