With the United Kingdom voting to leave the European Union today, the pound has lost considerable value against the dollar. Are Dorico retail prices fixed in US dollars and Euros and will the exchange rates instantaneously apply in this situation?
The UK is at least 2 years from exiting the EU.
In the UK, people are quite familiar with using the internet to buy products from European companies quoting prices only in Euros (or even from US companies quoting only USD prices). UK-issued credit cards don’t have any problem handling that - you just pay whatever the exchange rate is at the time.
Since Steinberg in based in Germany, I wasn’t at all surprised to see prices for Dorico quoted only in Euros.
It depends on the exchange rate of the BGP. UK users always had to deal with this. One better should wait until the GBP stops falling. 
Yes, Eurozone users should be on the lookout for deals over the next days and weeks … downloads that are priced in pounds sterling should be especially of interest.
One might be waiting a long time … 
The EU doesn’t look in such a good shape itself. It’s just lost its second biggest national economy and its biggest national defence budget. Opinion polls have claimed a “Frexit referendum” would give about 60% in favour of France leaving (and don’t forget that a bunch of French intellectuals more or less invented the concept of the EU!) and that could be a serious possibility after the 2017 elections. Not to mention the Netherlands and Sweden - and the economic problems of Greece, Italy, Portugal, etc, haven’t suddenly gone away…
Don’t forget the UK has some past history over this. When Henry VIII declared “RomeExit” back in 1536, the result turned out pretty well in the long term 