I found a bug in v0.9.0 with the "user one same location - random engine" and the "?poster_map=$UID".
The Randomizer is working very well until jo jump to a user by clicking f.e. in his profile to go to the map with "user_map.php?poster_map=$USERID".
Then there are user which should original be randomed at their location missing on the map.
Have a look at this, i jumped to UID 34 (Stefan) by clicking in his profile on the location (linked to user_map):

Here the look without using "poster_map":

If you need more information please let me know

Ben