i just also launch c10t and the .png is black

with --debug option, i get this text :
/home/minecraft/serveur/world/region/r.-1.1.mca(-15,47): dequeued OK

and in c10t.log, i got :
"/home/minecraft/serveur/world/region/r.-1.-4.mca(-17,-116)": Not a valid tag type
during 17999 lines with region and x/y changing