question

My assumption on why this is happening is that the processor will only receive a new item when another exits when the current content is equal to the maximum content. If the current content is less, the input should already be open and so the processor should normally not receive another item (since it would then have two pending inputs).

To 'jumpstart' the processor again, call receiveitem() on it, when increasing the max content past its current content if the processor's input is currently closed.

Object processor = Model.find("Processor1");
int newMaxValue = 10;
processor.setProperty("MaxContent", newMaxValue);
if(!ipopen(processor, 1) && processor.subnodes.length < newMaxValue)
{
    receiveitem(processor, 1);
}