So here is my second contact sheet, I think I did it bit better exposure wise.

first part :


on this part I think that the photo on the left should have had 1 stop more ligth, photo on the rigth look nearly ok, what do you guys think ?
second part :


This is the second sheet I printed, I notice that in some places, where I should see white, I get something like greyish, I think this is my dev that dektol that wasn't good anymore, am I rigth ?

Clearly the first photo here is overexposed, i think the other could have done maybe with 1/2 stop more.

for data : T-Max 400 @400 in D76 for 7,5 minutes

I will try to get a contact sheet printer for 120 as I'd like to have nice looking sheets too.

On a side note, I was more careful handling the paper so there are no stains from spilled fix on them too...

Regards and thanks you all for the help and advices