question

The popup in your original question uses the getstat() command. The getstat() command can return a giant number (STAT_UNDEFINED) if that stat isn't available. You can test this code in the script console, assuming you're using @Regan Blackett 's model:

int rack = 1;
double value = getstat(getactivity("ProcessFlow", "Zone"), "PartitionContent", STAT_CURRENT, 0, rack);
if (value >= STAT_UNDEFINED) {
    return 0;
}

return value;

At reset, the Zone doesn't have any partitions. So all Partition stats (like PartitionContent") aren't available. The partition isn't created until it's needed. So in Regan's example, Partition 1 doesn't exist until a token with Rack label 1 tries to enter. This may be happening to you.

Another possibility for this issue is that the instance is not correct. It looks like the pickoption just assumes "current", which means you are getting stats for the same instance as the token. In my code example, I passed a 0, because General Process Flows only have one instance, so that value is ignored. If you are trying to get statistics for an activity in an Object flow, where there is one instance per attached object, then you'd need to pass in the correct object there.

I think we should definitely see your model then. In my example model the first time the partition content is checked, the result is a properly reported zero.