Hello, regarding Cummins Insite 7.6, please note that it is quite an old version. If you use Windows 10 or later, I would recommend looking for a newer version such as 8.5 or 8.7, since 7.6 tends to have compatibility issues with current adapter drivers (such as the Nexiq USB Link 2).
Regarding Davie 4, it is a bit more difficult to get a stable version that works without the original PACCAR VCI. Some "cracked" versions work with generic J2534 interfaces, but for bench programming it is risky if you do not have the proper tool.
We suggest that you look in the Heavy Duty / Trucks section of the forum; that is where the download links or active tоrrеnts are usually found. Good luck!