Hello,
You live in 2012 year? Ok, back to the future.
"First Release: Feb 27, 2012"
http://www.exchangerates.org.uk/GBP-USD-27_02_2012-exchange-rate-history.html
1 GBP = 1.5831 USD
20 * 1.5831 = $31.662
I get ($35 - 10% - $0.5) $31 from every sale.
I'm not going to compare software/apps/plugins/etc. Just say it's a support topic.
Added already in v1.0.1.