Just as a reminder to myself

1. get the date from OSM
curl -L "http://www.informationfreeway.org/api/
0.5/map?bbox=10.427293,50.856042,10.551697,50.927502" -o data.osm

The numbers beeing lower left and upper right corner

2. split up the file in case it is to big (the one I used isn't, but the programm generates a nice template option file for mkgmap too)

java -Xmx1000m -jar splitter.jar data.osm

3. process with mkgmap to produce .img file (and with this options an gmapsupp.img for USB upload to the Garmin)

java -Xmx512M -jar mkgmap.jar --latin1 -c template.args --gmapsupp

curl, splitter and mkgmap are linked somewhere in the wiki and are availiable for windows

Next: routing support (need to convert osm file into polish format, but didn't find a tool to do this)

cheers