I have the very same problem. All I get when I start mappero is a blank screen with control buttons on it.
But:
1. it does not show any map tiles
2. does not show the traces (either the track or the routing trace)
3. does not show the blue filled circle where I am.

I tried to update and going back to previous version, I installed and uninstalled several times. But it does not change.

I even removed ~/.maemo-mapper but no effect.

Im stuck because mappero does not show any info, if I start from the terminal it has no output. So I dont know how could I debug a little further.

Im going to London for a week for slightseeing, and would be cool, if mappero works.

I downloaded "modrana", and it does find itself, and shows the map, but it is way more limited then mappero (especially it does not show any traces, where Im going...)

Any idea is most welcomed, also if there is a bugzilla for mappero, I would really like to know its url.

Best regards,
Laszlo