As to Flubaroo not running, several folks have reported it. I have contacted the writer of Flubaroo.
Some countries use a semicolon where we use a comma. You will have to use the proper separator for your country.
It can be difficult to test when grading with a formula. I suggest you create three students, one with all correct, one with all incorrect answers, and one with no answers.
I don't know how Flubaroo will handle a negative total answers. Before you create a formula for each question, you may want to create the formula for a couple of questions and then grade just those questions to see if Flubaroo produces the output you want.
If Flubaroo won't work, you can grade the sheet with formulas and use Autocrat to send the results. That is a very advanced method. Let me know if you want an example. It has been a long time since I used this method.