I originally posted this problem in General Discussion, but having re-read my error message I realised that I'm supposed to post the details here. Sorry!
I wasn't able to download BJ4 from the games page, the link was dead, so I downloaded it from grundislav's website. When I unzipped it and tried to run the game I got this message:
QuoteAn exception 0xC0000005 occured in ACWIN.EXE at EIP = 0x8FF98868 ; program pointer is -189, ACI version 2.62.772, gtags 0,0)
I'm wondering if the error was something to do with file paths rather than the game itself, because all of the html manual files were looking for images in a folder that doesn't exist on my computer, presumably the location they were in on the author's machine.
I'd appreciate any help with this, I'm so keen to play #4!
What version of Windows are you running?
This might be the GetFreeDiskSpace bug on Windows 98, that was fixed in AGS 2.7, in which case unfortunately your options for getting it working might be rather limited.
Thanks for such a speedy reply and sorry for such a late thank-you. I am indeed running Windows 98. The mystery is solvéd.
You could try attempting to run the game with a newer version of the engine and see if that gets around the problem.