strongly disagree, agree, disagree or strongly disagre
That's a fairly full range of options. Adding a 'don't know' would cause problems in calculating an accurate result.
For the abortion example you give, I suppose the best answer to the statement would be either a strong disagree or strong agree.
I do find the way a lot of the questions are angled to be more from the left though
As far as I know, it's written by political scientists, and the result isn't based on a yes/no to one or two questions, more on a synthesis of reaction to a number of subtle statements.
Macron is actually for more right wing than Le Penn,
Indeed. Le Pen is a National Socialist, whereas Emmanuel Macron favours freedom and a market economy.
Interestingly (and closer to the topic) I did a Polish language one recently, partly geared to issues within Poland. I'll have a look later and see if I can find it.
edit This isn't the one I did, rather it was prepared for the last GE in Poland. But maybe worth a look: parlamentarny.pl/barometr-wyborczy-2015/