[Components] ezcWorkflowNodeVariableSet vs. $execution->setVariable()?

Good Morning. ezcWorkflowNodeVariableSet vs. $execution->setVariable()? I'm trying to get my arms around when I'd use each. At first I thought that the ezcWorkflowNodeVariableSet is part of workflow definition whereas the $execution->setVariable() is available when workflow is executing ... but

[Components] I can't see why this throws exception?

Another newbie situation :-) I get an exception on resume(). It is noted in following code as a comment. The classes PrintTrue and PrintFalse exist, code also below. As expected, the workflow suspends ... waiting for input. But when provided the input via resume(), it throws exception ... Unde

[Components] Struggling a bit w/ ezcWorkflow

Hi, I'm new to ezComponents/ezWorkflow. Trying to get a simple example to run using ezcWorkflowDatabaseExecution. It kabooms because I don't have the required tables in my database. Makes sense ... I didnt create any tables :-) I'm having trouble finding any info on schema for tables required.