We used to have a scheduled chat every Saturday and encourage members to come, but finding a time where members from all corners of the world could meet at once was troublesome, to say the least, so we no longer encourage the chat too often. Instead, we recommend that you participate here in the forums instead; that way, any member can see what you've written at any time of day.
If you are in the chat room, you might find the shoutbox useful for inviting other members. If there are other members online, leave a message in teh shoutbox like "Join me for a chat!"
Finally, there is a flaw in this version of FlashChat that occassionally shows a person online who in fact is not online, which may be why they are not replying to you. When you log on, Flash Chat sends you the list of members who is online, but the flaw is that that list is usually outdated, and sometimes includes the last member or two who was also online. The name disappears after your computer queries the chat for an update and realizes that person is no longer there. So don't worry, they're not being rude.