Branching is achieved with Events. You can use Logic Actions like Float Compare, Bool Test, or world tests like Game Object is Visible or Trigger Event to send events and branch your behaviour.
See attached image.
| If var1 > 0, do a thing?
Use Float Compare to send an event and transition to the "do a thing" state.
| is there a concept of "else" or "else if" when comparing variables?
Actions are executed in order, if an action doesn't trigger an event then the next action runs, which works like an "else."
Or you can use multiple states with TRUE/FALSE branching to express the algorithm like a flowchart. This is more work to setup, but is easier to follow and often exposes holes in your logic!
| If var1 > 0 && var2 > 0 && var3 > 0 && var4 > 0, do a thing.
Either use multiple states as described above.
Or the new Conditional Expression Action (Beta):
http://hutonggames.com/playmakerforum/index.php?topic=7337.msg35523#msg35523But I would encourage you to consider multiple states. It makes the algorithm clearer and helps you debug edge cases. You can also see the flow at runtime in the graph view and in the FSM Log. You can even pause the game and step back through all the state changes and examine variables etc.
It you want to collapse the states into their own graph you can use the Run FSM action: Make an FSM that does only the work you need and expose variables with the Inspector flag. Save this FSM as a template and you can run it at any time using Run FSM. Inspector variables will appear as parameters in the Run FSM action, so you can expose input parameters but keep the implementation details hidden inside the template. Essentially this lets you make your own actions inside Playmaker.