Hi there, 
I have amended the Alcohol Stroop task to suit my needs, and it's working great. 
Currently, it is running with two blocks (Each block repeats the word list 2 times, leading to a total of: 40 critical words + 40 control words per block). However, I would like instead to have 4 blocks, with each block running the list just once (20 words per list), so it would like like:
Block 1: 20 critical, 20 control
Block 2: 20 critical, 20 control
Block 3: 20 critical, 20 control
Block 4: 20 critical, 20 control 

Essentially the overall total of words won't change (2 blocks =160 total, or 4 blocks=160 total), but the participant would get a short break between each block . I have tried amending the highlighted part below but it hasn't been able to run. 

Does anyone have suggestions on which part of the script I would need to edit to get the task to run the way I would like it to? I am sure there is a very simple solution, but I am extremely new to this so it's all mind-boggling to me. 
Thank you in advance for your assistance!
stefania 

Reduce the number of trials in the respective <block>'s /trials attribute to 40. Edit the <expt> element to run 4 blocks instead of only two.

<expt>
/ blocks = [
    1 = StartInfo;
    2 = Practice;
    3= AlcoholStroop;
    4 = Rest;
    5 = AlcoholStroop;
    6 = Rating;
]
/ postinstructions = (end)
/onexptend = [values.completed = 1]
</expt>

becomes something like

<expt>
/ blocks = [
    1 = StartInfo;
    2 = Practice;
    3 = AlcoholStroop;
    4 = Rest;
    5 = AlcoholStroop;
    6 = Rest;
    7 = AlcoholStroop;
    8 = Rest;
    9 = AlcoholStroop; 
   10 = Rating;
]
/ postinstructions = (end)
/onexptend = [values.completed = 1]
</expt>