Actually, only one waypoint is needed to graduate the grid. For example, the rectangular coordinates of Louhi railway station are 502905, 7331395 (provided that latitude origin=0deg, longitude origin=33deg, false easting=500000m, false northing=0m, map datum=Pulkovo-1942).

By the way, you can download 1:200000 maps containing some nodes of the deg/min grig, which can be easily used for calibration. The maps can be downloaded from [www.velotourism.ru] (files are large).

I cannot make any (visible) difference between Pulkovo 1942 (1) and (2), both of these settings are relevant for Russian maps.

Good luck!