Disregarding your triple post for now, I'll answer a few questions in a random order for your enjoyment.
The reason why you must select a CD-ROM drive even though you are using a mounted image is quite simple. Daemon Tools emulates a CD/DVD-ROM drive, hence it works exactly the same way as a normal CD/DVD drive would (with a few differences of course). Chankast needs to know where to look for data, so you need to choose the Daemon Tools drive as the drive to use as a Cd-ROM drive. Pretty simple, no?
If you have problems with ASPI, switch to the CdRom xxx plugin. However, in many cases that won't probably remove the fact that Chankast still recognizes the image as an audio CD. Personally, I use Daemon Tools 4 and never had such a problem, nor so I know why Chankast detects some games as a simple audio CD.
It would be better if you had access to more games, so that you could test if the problem is just in the image itself.