The problem is the PKM files you are using are size 136.
Gen 3 PKM files are 80 or 100 bytes, and Gen 1 and 2 PKM files even smaller.
Where did you get these PKM files from, are they from a later game or editor for later generation?
Only Gen 3 PKM files generated by A-Save, Encycopedia Pokemonica and this editor are supported.
Version 4.2 will display an explicit message when given a file of incorrect size. It's not a bug however.
Thanks, now i know why! There is a way to convert this .pkm files to a smaller capable of run in your software? Cause this files open on Pokegen, but not on your editor!