Now i found this entry on forum:
Just for those interested... Picodrive
download on Wololo's top 15 VHBL games seems to not let you select a ROM, I downloaded 1.51
and bingo straight away my Megadrive ROM's worked perfectly!
I will test the 1.51 version
when i be back home today, i also have downloaded the 1.35 version
from wololo`s 15 Essential Homebrews.