geco SkySubDivision Upper limit / large scene?

hi all,

at the moment i try to deal with the solaraccess, it is a large scene i want to analyze.
all works fine, if i have a skysubdivision [s] = 50... ecotect analyze the data and give them back to grasshopper.
in the time while ecotect analyze grasshopper and rhino are frozen, what should be normal.

if i try to set the skysubdivision to 40 or lower, ecotect start to analyze, rhino and grasshopper get frozen.
but before ecotect has finished the analysis, grasshopper awake, ecotect is still analyzing...and no data come back from ecotect to grasshopper...

what did i wrong? is there a upper limit on accuracy which can not be handled by grasshopper?

thx.