Cannot initialise the map

[routeconverter]

Could not initialize the map
Possible solutions:
1. You are using a ?-bit RouteConverter with a 32-bit Java which is not compatible. Download a RouteConverter version that matches your Java version.
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So, my question is, why has this happened

I guess something has changed on your machine. Most likely, you've installed Java 7 from Oracle?

and which version of RouteConverter should I download?

Try the 64-bit version for RouteConverter 2.13 which I've release last friday.

I have a 64-bit OS system and Java seems to install regular updates without noticing me (latest one possibly on 14/07/2014).

That could be the change on your machine.