Burning a DVD-RAM DL, which program and how-to ?

[Bols]

Hi, i need to burn a .iso size 6.5 GB to a DL DVD.

All i have here is a Panasonic DVD-RAM DL 3-5xspeed for video recording

I have tried literally every option in Nero 7 Essentials, but it always tells me the disk is too small...

It says : Disktype required : DVD R/RW; DVD R DL; DVD-RAM
Disktype entered : DVD-RAM

Don't get what's not working. Is it the DVD or do I need to do something else to start a DL burning sequence to maybe set the point of sideflip manually ... Not sure ?

I have searched google, but can't find any good info related to this kind of DVDs

Any help appreciated thanks