Hi,
To support the map input, that'll drive the Animation Offset, the "Animate Scale by Age" effect should be modified in the following way (please find attached the complete .eff file):
vector offsetMapAmount = evaluateTexture(OffsetMap,fpItem.distUVW); real randomStartTime = randomReal(RandomStart, RandomEnd)+(OffsetStart*offsetMapAmount.x);
real TimeInSecs = Max.time/4800.0;
real ActiveTime = if(TimeInSecs>randomStartTime,TimeInSecs-randomStartTime,0.0);
real timePosition = min(1,ActiveTime/SecondsToAnimate);
real newScale = evaluateCurve(XYZ_Scale,timePosition);
fpItem.scale = [newScale,newScale,newScale];
Just please take in mind, the "OffsetStart" parameter should be set to any "non-zero" value.
I hope that helps.
Best regards,