Item 1, I'm not sure what is going on.  BExR doesn't use a central server.  The application connects to the exchanges listed on the "about" page and downloads rates directly from them.  It seems odd that you would be blocked from all of them.  All I can suggest there is to check your settings.

Item 2, not all exchanges carry all currency pairs.  Because of this, the list of exchanges has to be reset each time you change either the source currency or destination currency.  I'll see about adding in an option to keep the same exchange if it is still valid after you change the currency, but as it doesn't keep the program from working it won't be a high priority.

Glad you like the widget!