Hi I'm trying to compile a map of Iberia with DEM and Contours but getting the following assertionError can someone give e a hint of what might be wrong? Number of MapFailedExceptions: 0 Exception in thread "main" java.lang.AssertionError: 226391 at uk.me.parabola.imgfmt.app.BufferedImgFileWriter.put2u(BufferedImgFileWriter.java:164) at uk.me.parabola.imgfmt.app.trergn.Zoom.write(Zoom.java:81) at uk.me.parabola.imgfmt.app.trergn.TREFile.writeMapLevels(TREFile.java:214) at uk.me.parabola.imgfmt.app.trergn.TREFile.writeBody(TREFile.java:122) at uk.me.parabola.imgfmt.app.trergn.TREFile.write(TREFile.java:341) at uk.me.parabola.mkgmap.build.MapBuilder.makeMap(MapBuilder.java:301) at uk.me.parabola.mkgmap.combiners.OverviewBuilder.writeOverviewMap(OverviewBuilder.java:192) at uk.me.parabola.mkgmap.combiners.OverviewBuilder.onFinish(OverviewBuilder.java:104) at uk.me.parabola.mkgmap.main.Main.endOptions(Main.java:675) at uk.me.parabola.mkgmap.CommandArgsReader.readArgs(CommandArgsReader.java:125) at uk.me.parabola.mkgmap.main.Main.mainStart(Main.java:144) at uk.me.parabola.mkgmap.main.Main.main(Main.java:115) Thanks a lot Joao