You should consult an attorney - and one that deals with business litigation because I do see you having to litigate this if you want to get paid.

Generally, if you have some type of agreement, but the agreement does not cover a particular provision, the court (or arbitrator) will go to default provisions. I'm sure there are some default rules for partnership agreements - for contracts in general it is the UCC.

Because this is international, it sounds like you'll be in federal court. Just a clarification though - you said the agreement was signed in Africa, the investors are from the UK, but the business was here right? Unfortunately, you may not even be able to sue here at all because of jurisdictional issues. But, talk to an attorney to figure that out.

No, this is generally not the way that things are split up in the end.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~