The Wacom tablet is capable of sensing and transmitting changes to the pen position at greater than 1000 updates per second. If the Capytalk expressions in your Multigrid are complex, evaluating these expressions at such a high rate could cause the Paca(rana) to get behind and fall out of real time.
Have you tried increasing the input-to-output delay (found in the Configure drop-down menu in the DSP Status window)? For the Wormhole, we recommend setting it to 14 milliseconds.