Parley promotion mechanism for vocabulary

[Jürgen]

Parley promotion mechanism for vocabulary
Ubuntu 16.04 64bit with Parley version 2.1 Using: KDE Frameworks 5.28.0 
Qt 5.6.1 (built against 5.6.1) The xcb windowing system

Dear All,
Congratulations to you all for making a software like Parley possible. I 
am using it since many years for learning Spanish. I have also uploaded 
a vocabulary file with 4000 words English/Spanish.

Where I am at a loss and I can't find any information on the web is how 
the promotion of the vocabulary functions. In my daily learning some 
words they repeat and repeat and repeat and simply can't get out of the 
loop anymore. Sometimes I have out of 100 words 30 that simple hang out 
although I have already answered them several times correctly.

I have already disable the 3x correct option to be valid. Many times a 
word comes in new, gets then processed as correct and repeats as level 2 
word. Then it comes the next time, is correct answered and then Parley 
is closed and the files is saved (Parley is configured to save the files 
before closing). But then the next day the word comes again as level 1 
word and promoted to level 2 but this goes on indefinitely. The word is 
stuck.

Can somebody explain how the promotion of words is intended to work? In 
the data file there are 4 categories:

pregrade
currentgrade
count
errorcount

Is there any connection between errorcount and currentgrade?

I appreciate to get some light on this issue.
Greetings
Juergen