I hope this is an appropriate post for this list. Since I updated my Garmin Etrex 20 to the latest firmware (4.30 [http://www8.garmin.com/support/download_details.jsp?id=5553]), I have had problems with routing with OSM maps generated with mkgmap. So far, I have only tried standard maps from http://garmin.openstreetmap.nl/ and http://extract.bbbike.org/. (My previous quick attempts to run mkgmap directly failed after I was unable to find documents that explained the process sufficiently clearly, although I may now need to try again after this problem.) Trying various routes that had always worked with previous versions of the firmware, I get a variety of symptoms including: 1) Apparent deadlocks (requiring batteries to be removed to achieve reboot); 2) "Route calculation error"; 3) "The route does not match the available maps. Cannot follow the roads precisely. Do you want to recalculate the the route?" Choosing [Yes] gives "Route calculation error. Maps do not have routable roads in this area." A quick google search only showed one similar very brief report of similar problems (although not with mgkmap/OSM so far as I could tell) after firmware 4.30 was installed. Is this a known problem? Garmin certainly changed more than they documented on this firmware revision: for example version 4.30 could not read Waypoint files written by previous versions. Thanks for any help on this. If I can help with diagnosis, please let me know. ael