I finally managed to download the trainer from the megaupload link and indeed, I started getting all of those runtime errors 424. But when I tried the trainer from the original attachment, everything seemed to work fine.
Here's what happens when I try the same game for the two different files:
Megaupload Link
Original Attachment
So anyway, I'm going to take a wild guess and say that there's a problem with the megaupload link. My solution for the moment would be to download the trainer from this link instead:
http://www.sendspace.com/file/com8wz
I personally uploaded the original attachment there so, hopefully it might help solve the problem for some. If it doesn't however, I'll try to find other solutions. For the moment, try out the link, play Dubloon Disaster and let me know if it works for any of you.