I burnt a bit of Midnight oil last night so I pleased to announce a trial version of the "Club Arnage Lolly Leveler" (Call) is ready to try.
It's an Excel spredsheet. Currently all fields are unlocked so there is great opportunites for you to mess it up.
But if you read the instructions below you should be fine.
First it has some limitations.
Only 6 people are supported.
Only 7 transactions are supported.
Only 2 currencies are supported.
how to use it:-
Sheet one "Balances".
Change "name1", "name2" and so on to the people in your group.
Enter the exchange rate in cell B5 That will alter all of the exchange rates.
Enter the number of shares each personis responsible for.
Don't Change anything else on that page.Sheet 2 " Outgoings".
Change the names to names of the people under "Paid by"
Note: if you changed name1 one Balances to say "Harry" you don't have to change name1 here to the same it can be any of the names you entered.Change the Currency sign under currency either € or £.
Allter the amount as required.
Don't Change anything else on that page.Sheet 3 "Spend"
Look but don't touch 
You should see that as you change names, Currency, and Amounts on "Outgoings" you should find that Balances adjusts the amounts owed to or by each person.
Ith e amount is
Red then the kitty owes that person the money. If it's Black then that Person owes the Kitty money.
So does it do what you want?
Download Call from
http://lemans.tmdg.co.uk/Call.xls t