First of all, I want to thank Steinar of making and maintenance this great software! I am quite new and just testing it, but it is really great work!
Back to subject - I trying to work with HTTP communicate processor. It allows populate single variable (BTW. not the first one on list of user variables, it seems like little bug

For example: if response from another application through JSON will return:
{ 'val1' : 'first value content', 'val2' : 'second value content' }
I did not find any function in Populate Variables processor which can help me with that (besides using substring functions on static indexes) but it is of course impossible to predict length of first value etc.
Maybe someone already know solution and I just missed something really obvious in documentation?
Regards,
Artur