[sublynx]

here's the relevant part from my data/menu/cfg/maps.cfg file. You can open yours with Notepad. You can try changing the line ZoomLevels=1,2,5,... etc to see if that solves the problem. I have never tried OLC Gui so I have no idea if doing this would cause other problems in that GUI, so take a backup copy of your maps.cfg before fiddling around with it.

[Map0]
MapID=Navigation_map
Position=0,0
Resolution=1024,656
MajorSqrs=4,2.4
MinorSqrs=5,5
PixPerUnit=50
ZoomLevels=1,2,5,10,20,50,100,200,500,1000,2000,40 00,7000,10000,20000,40000; meters per pixel
InitialZoom=20000
SymbolZoom=20000;units are drawn as symbols from this zoom up
GroupsZoom=40000;units are drawn in groups from this zoom up
CityZoom=10000;city names are displayed from this zoom down
KriegZoom=2000;krieg labels are separated displayed from this zoom up
HarborZoom=50;harbors will be displayed from this zoom up

[Map1]
MapID=Attack_map
Position=0,0
Resolution=1060,768
MajorSqrs=4,2.9
MinorSqrs=5,5
PixPerUnit=50
ZoomLevels=1,2,5,10,20,50; meters per pixel
InitialZoom=2
SymbolZoom=20;units are drawn as symbols from this zoom up
GroupsZoom=20;units are drawn in groups from this zoom up