Right, having read through all the answers I got regarding the time-limit thing when it came to posting before I need to move the thing forward myself I have come to the following conclusion: I propose three days (that is, 72 hours since last post was submitted) of time to send in a reply, with a 4th one (up to 96) thrown in during out of combat situations. I don't really expect long posts as this is merely on casual level and the way how D&D works does not exactly call for large posts anyway. If you have anything against this proposition, speak up! It's but an idea.
Also, some information about the game itself. The story will begin in the town of Greenest, south-east of Baldur's Gate in the southern end of the Sword Coast. It is mostly surrounded by plains, but there are some forests nearby as well. You people need to figure out a reason for your characters to be around there... one of the suggestions I have is to be a caravan guard/passenger in one of the caravans that happened to be heading there. If you want some of your characters to know each other beforehand, that is fine too! Feel free to think this through, I'll see if we are ready to begin on Sunday.