I had a go at entering a purchase from the Receipt Hub for an invoice in Euros, but although I entered the amount in Sterling that the purchase cleared the bank account this was ignored/over-written and the four decimal place exchange rate was used (so out by a penny).
There is ceiling of around 230,00€ were after this figure there is a possibility that the exchange rate will calculate the invoice with rounding up/down out by a penny.
230,00€ @ 1.1305 = £203.45 (£203.4498)
230,00€ @ 1.1306 = £203.43 (£203.4318)
To calculate an invoice to equal £203.44
230,00€ @ 1.130554 = £203.44
We have previously discussed this issue as a feature, but really to me this should marked up as a bug.