Termination during a probationary period for a permanent contract

Hello,

Here I am looking for help that I couldn't find online.
Let me explain the situation.
I worked for a coffee vending machine company in Grenoble.
I signed a fixed-term contract from February 15, 2010 to August 31, 2010.
I wasn't sure if I wanted to stay because there were some shady things within the company,
but on the other hand, it's a permanent contract so I didn't know what to do.
At the end of this fixed-term contract, I asked my manager to extend the contract by one month to be sure. Additionally, during this fixed-term period, he added work that has nothing to do with what I initially signed for, so I took the liberty of telling him that I didn't think it was fair to add work to my plate when I already had plenty to do... So he promised me that I would receive certain commissions if I managed to complete the extra work he asked for. He then made me sign an amendment to the contract to extend my contract until September 31, 2010...
Today is October 6, 2010 and I haven't
1- signed a work contract
2- the promise he made me regarding my commissions was made orally (no documentation)
3- I just received an offer for another permanent contract with another company that I really care about.

So my questions are as follows:

1- Is there a probation period for permanent contracts? If so, how long is it?
2- If I terminate my probation period, will I lose all my paid leave that I have accumulated from February 2010 to September 2010? Or will I still be entitled to it?
3- If I terminate, will it affect my unemployment benefits?
4- Should I really count on the promises he made me?

THANK YOU in advance for your responses.
Have a great end of the day.
Best regards

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