Yes Haree78, I actually did.

I think i will stick with 20 races so that if someone try my mod one day I'm sure it won't crash because of the same situation.

<r> Thank you tjhkkr.<br/>
<br/>
I finally solved the problem !<br/>
And... it seems that it had nothing to do with the images.<br/>
<br/>
First, when i tried STPE, I removed some races without changing anything about the pictures, and the error message was still there.<br/>
This morning, i ...

Thank you for the advice.
I removed the concerned policy files but the problem is still there...

<t> Don't worry for the french part, what it says is not really important or easy to understand :<br/>
"La valeur ne peut pas être null" = "the value can't be null".<br/>
It seems like it's talking about an image.<br/>
All my images are 300x300, and don't seem to have any problem.<br/>
<br/>
So ...

Thank you for your answer

...does the id of the race in the biases file have to be the same than the picture id ?

<t> Here is more information, if it can help :<br/>
<br/>
Consultez la fin de ce message pour plus de détails sur l'appel du débogage<br/>
juste-à-temps (JIT) à la place de cette boîte de dialogue.<br/>
<br/>
************** Texte de l'exception **************<br/>
System.ArgumentNullException ...

<r> Hi,<br/>
<br/>
I'm trying to realise my first mod.<br/>
I'd like to just add some races for the moment.<br/>
But when I switch the theme, here is the error message i get :<br/>
<br/>
<IMG src="http://image.noelshack.com/fichiers/2012/21/1338023837-dw.png"><s>[img]</s><URL url="http://image ...